Global ETD Search

1	Physiological and molecular changes associated with alterations of sulphur status in sugar beet (Beta vulgaris L.) Thomas, Steve January 2001 (has links) No description available. 630 Yield; Quality; Growth; Metabolism
2	Effect of Lygus bugs (Hemiptera: Miridae) on field beans in Manitoba NAGALINGAM, THARSHINIDEVY 04 1900 (has links) Lygus lineolaris (Palisot de Beauvois), L. elisus (Van Duzee), L. borealis (Knight) and Adelphocoris lineolatus (Goeze) were the major species of plant bugs present in commercial field bean and soybean fields in 2008–2010. Lygus lineolaris comprised 78–95% of the mirid adults and <10% were A. lineolatus. Lygus lineolaris reproduced in field beans and completed a single generation. In field beans, adults entered the crop in late July, corresponding to growth stages from late vegetative to pod initiation, and females laid eggs in the crop. Nymphs hatched and developed and were most numerous at the seed development and seed filling stage. At seed maturity, late instar nymphs and adults were present. In soybeans, L. lineolaris reproduced but nymphs had poorer survival than in field beans. Late in the season, adult numbers greatly increased in field beans and soybeans, partly due to immigration of adult Lygus bugs from early‐maturing crops. Field beans and soybeans appeared to be a transient host for A. lineolatus. There were no effects on yield quality or quantity associated with the numbers of plant bugs seen in field surveys. In laboratory and field cages, the type of injury from L. lineolaris feeding differed among plant growth stages but not between nymphs and adults, although nymphs generally were more injurious. At flowering to pod initiation, abortion of buds, flowers or pods was the most common response to feeding injury; pod abortion did not occur when injury occurred at later growth stages. Sometimes abortions resulted in reduced yield quantity, but sometimes plants compensated for the injury. No loss of seed quality occurred from feeding at this stage. During seed development and filling, feeding injury most frequently affected the vascular supply to filling seeds, resulting in shriveled seeds and pods at harvest, and consequent reduced total harvested seed weight. At seed maturity, direct seed injury, involving penetration of the testa and loss of cotyledon tissue, was the most frequent injury and resulted in pits in the seed coat at harvest. There was no loss in yield quantity when feeding occurred at seed maturity, but seed pitting reduced yield quality. / May 2016
3	Effect of temperature and photoperiod on broccoli development, yield and quality in south-east Queensland Tan, Daniel Kean Yuen January 1999 (has links) Broccoli is a vegetable crop of increasing importance in Australia, particularly in south-east Queensland and farmers need to maintain a regular supply of good quality broccoli to meet the expanding market. However, harvest maturity date, head yield and quality are all affected by climatic variations during the production cycle, particularly low temperature episodes. There are also interactions between genotype and climatic variability. A predictive model of ontogeny, incorporating climatic data including frost risk, would enable farmers to predict harvest maturity date and select appropriate cultivar - sowing date combinations. The first stage of this research was to define floral initiation, which is fundamental to predicting ontogeny. Scanning electron micrographs of the apical meristem were made for the transition from the vegetative to advanced reproductive stage. During the early vegetative stage (stage 1), the apical meristem was a small, pointed shoot tip surrounded by leaf primordia. The transitional stage (stage 2) was marked by a widening and flattening to form a dome-shaped apical meristem. In the floral initiation stage (stage 3), the first-order floral primordia were observed in the axils of the developing bracts. Under field conditions, the shoot apex has an average diameter of 500 micro m at floral initiation and floral primordia can be observed under a light microscope. Sub-zero temperatures can result in freezing injury and thereby reduce head yield and quality. In order to predict the effects of frosts, it is desirable to know the stages of development at which plants are most susceptible. Therefore, the effects of sub-zero temperatures on leaf and shoot mortality, head yield and quality were determined after exposure of plants to a range of temperatures for short periods, at different stages of development (vegetative, floral initiation and buttoning). Plants in pots and in the field were subjected to sub-zero temperature regimes from -1 C to -19 C. Extracellular ice formation was achieved by reducing temperatures slowly, at a rate of -2 C per hour. The floral initiation stage was most sensitive to freezing injury, as yields were significantly reduced at -1 C and -3 C, and shoot apices were killed at -5 C. There was no significant yield reduction when the inflorescence buttoning stage was subjected to -1 C and -3 C. Although shoot apices at buttoning survived the -5 C treatment, very poor quality heads of uneven bud size were produced as a result of arrested development. The lethal temperature for pot-grown broccoli was between -3 C and -5 C, whereas the lethal temperature for field-grown broccoli was between -7 C and -9 C. The difference was presumably due to variation in cold acclimation. Freezing injury can reduce broccoli head yield and quality, and retard plant growth. Crop development models based only on simple thermal time without restrictions will not predict yield or maturity if broccoli crops are frost-damaged. Field studies were conducted to develop procedures for predicting ontogeny, yield and quality. Three cultivars, (Fiesta, Greenbelt and Marathon) were sown on eight dates from 11 March to 22 May 1997, and grown under natural and extended (16 h) photoperiods in a sub-tropical environment at Gatton College, south-east Queensland, under non-limiting conditions of water and nutrient supply. Daily climatic data, and dates of emergence, floral initiation, harvest maturity, together with yield and quality were obtained. Yield and quality responses to temperature and photoperiod were quantified. As growing season mean minimum temperatures decreased, fresh weight of tops decreased while fresh weight harvest index increased linearly. There was no definite relationship between fresh weight of tops or fresh weight harvest index and growing season minimum temperatures greater than 10 C. Genotype, rather than the environment, mainly determined head quality attributes. Fiesta had the best head quality, with higher head shape and branching angle ratings than Greenbelt or Marathon. Bud colour and cluster separation of Marathon were only acceptable for export when growing season mean minimum temperatures were less than 8 C. Photoperiod did not influence yield or quality in any of the three cultivars. A better understanding of genotype and environmental interactions will help farmers optimise yield and quality, by matching cultivars with time of sowing. Crop developmental responses to temperature and photoperiod were quantified from emergence to harvest maturity (Model 1), from emergence to floral initiation (Model 2), from floral initiation to harvest maturity (Model 3), and in a combination of Models 2 and 3 (Model 4). These thermal time models were based on optimised base and optimum temperatures of 0 and 20 C, respectively. These optimised temperatures were determined using an iterative optimisation routine (simplex). Cardinal temperatures were consistent across cultivars but thermal time of phenological intervals were cultivar specific. Sensitivity to photoperiod and solar radiation was low in the three cultivars used. Thermal time models tested on independent data for five cultivars (Fiesta, Greenbelt, Marathon, CMS Liberty and Triathlon) grown as commercial crops on the Darling Downs over two years, adequately predicted floral initiation and harvest maturity. Model 4 provided the best prediction for the chronological duration from emergence to harvest maturity. Model 1 was useful when floral initiation data were not available, and it predicted harvest maturity almost as well as Model 4 since the same base and optimum temperatures of 0 C and 20 C, respectively, were used for both phenological intervals. Model 1 was also generated using data from 1979-80 sowings of three cultivars (Premium Crop, Selection 160 and Selection 165A). When Model 1 was tested with independent data from 1983-84, it predicted harvest maturity well. Where floral initiation data were available, predictions of harvest maturity were most precise using Model 3, since the variation, which occurred from emergence to floral initiation, was removed. Prediction of floral initiation using Model 2 can be useful for timing cultural practices, and for avoiding frost and high temperature periods. This research has produced models to assist broccoli farmers in crop scheduling and cultivar selection in south-east Queensland. Using the models as a guide, farmers can optimise yield and quality, by matching cultivars with sowing date. By accurately predicting floral initiation, the risk of frost damage during floral initiation can be reduced by adjusting sowing dates or crop management options. The simple and robust thermal time models will improve production and marketing arrangements, which have to be made in advance. The thermal time models in this study, incorporating frost risk using conditional statements, provide a foundation for a decision support system to manage the sequence of sowings on commercial broccoli farms.
4	Effect of temperature and photoperiod on broccoli development, yield and quality in south-east Queensland Tan, Daniel Kean Yuen January 1999 (has links) Broccoli is a vegetable crop of increasing importance in Australia, particularly in south-east Queensland and farmers need to maintain a regular supply of good quality broccoli to meet the expanding market. However, harvest maturity date, head yield and quality are all affected by climatic variations during the production cycle, particularly low temperature episodes. There are also interactions between genotype and climatic variability. A predictive model of ontogeny, incorporating climatic data including frost risk, would enable farmers to predict harvest maturity date and select appropriate cultivar - sowing date combinations. The first stage of this research was to define floral initiation, which is fundamental to predicting ontogeny. Scanning electron micrographs of the apical meristem were made for the transition from the vegetative to advanced reproductive stage. During the early vegetative stage (stage 1), the apical meristem was a small, pointed shoot tip surrounded by leaf primordia. The transitional stage (stage 2) was marked by a widening and flattening to form a dome-shaped apical meristem. In the floral initiation stage (stage 3), the first-order floral primordia were observed in the axils of the developing bracts. Under field conditions, the shoot apex has an average diameter of 500 micro m at floral initiation and floral primordia can be observed under a light microscope. Sub-zero temperatures can result in freezing injury and thereby reduce head yield and quality. In order to predict the effects of frosts, it is desirable to know the stages of development at which plants are most susceptible. Therefore, the effects of sub-zero temperatures on leaf and shoot mortality, head yield and quality were determined after exposure of plants to a range of temperatures for short periods, at different stages of development (vegetative, floral initiation and buttoning). Plants in pots and in the field were subjected to sub-zero temperature regimes from -1 C to -19 C. Extracellular ice formation was achieved by reducing temperatures slowly, at a rate of -2 C per hour. The floral initiation stage was most sensitive to freezing injury, as yields were significantly reduced at -1 C and -3 C, and shoot apices were killed at -5 C. There was no significant yield reduction when the inflorescence buttoning stage was subjected to -1 C and -3 C. Although shoot apices at buttoning survived the -5 C treatment, very poor quality heads of uneven bud size were produced as a result of arrested development. The lethal temperature for pot-grown broccoli was between -3 C and -5 C, whereas the lethal temperature for field-grown broccoli was between -7 C and -9 C. The difference was presumably due to variation in cold acclimation. Freezing injury can reduce broccoli head yield and quality, and retard plant growth. Crop development models based only on simple thermal time without restrictions will not predict yield or maturity if broccoli crops are frost-damaged. Field studies were conducted to develop procedures for predicting ontogeny, yield and quality. Three cultivars, (Fiesta, Greenbelt and Marathon) were sown on eight dates from 11 March to 22 May 1997, and grown under natural and extended (16 h) photoperiods in a sub-tropical environment at Gatton College, south-east Queensland, under non-limiting conditions of water and nutrient supply. Daily climatic data, and dates of emergence, floral initiation, harvest maturity, together with yield and quality were obtained. Yield and quality responses to temperature and photoperiod were quantified. As growing season mean minimum temperatures decreased, fresh weight of tops decreased while fresh weight harvest index increased linearly. There was no definite relationship between fresh weight of tops or fresh weight harvest index and growing season minimum temperatures greater than 10 C. Genotype, rather than the environment, mainly determined head quality attributes. Fiesta had the best head quality, with higher head shape and branching angle ratings than Greenbelt or Marathon. Bud colour and cluster separation of Marathon were only acceptable for export when growing season mean minimum temperatures were less than 8 C. Photoperiod did not influence yield or quality in any of the three cultivars. A better understanding of genotype and environmental interactions will help farmers optimise yield and quality, by matching cultivars with time of sowing. Crop developmental responses to temperature and photoperiod were quantified from emergence to harvest maturity (Model 1), from emergence to floral initiation (Model 2), from floral initiation to harvest maturity (Model 3), and in a combination of Models 2 and 3 (Model 4). These thermal time models were based on optimised base and optimum temperatures of 0 and 20 C, respectively. These optimised temperatures were determined using an iterative optimisation routine (simplex). Cardinal temperatures were consistent across cultivars but thermal time of phenological intervals were cultivar specific. Sensitivity to photoperiod and solar radiation was low in the three cultivars used. Thermal time models tested on independent data for five cultivars (Fiesta, Greenbelt, Marathon, CMS Liberty and Triathlon) grown as commercial crops on the Darling Downs over two years, adequately predicted floral initiation and harvest maturity. Model 4 provided the best prediction for the chronological duration from emergence to harvest maturity. Model 1 was useful when floral initiation data were not available, and it predicted harvest maturity almost as well as Model 4 since the same base and optimum temperatures of 0 C and 20 C, respectively, were used for both phenological intervals. Model 1 was also generated using data from 1979-80 sowings of three cultivars (Premium Crop, Selection 160 and Selection 165A). When Model 1 was tested with independent data from 1983-84, it predicted harvest maturity well. Where floral initiation data were available, predictions of harvest maturity were most precise using Model 3, since the variation, which occurred from emergence to floral initiation, was removed. Prediction of floral initiation using Model 2 can be useful for timing cultural practices, and for avoiding frost and high temperature periods. This research has produced models to assist broccoli farmers in crop scheduling and cultivar selection in south-east Queensland. Using the models as a guide, farmers can optimise yield and quality, by matching cultivars with sowing date. By accurately predicting floral initiation, the risk of frost damage during floral initiation can be reduced by adjusting sowing dates or crop management options. The simple and robust thermal time models will improve production and marketing arrangements, which have to be made in advance. The thermal time models in this study, incorporating frost risk using conditional statements, provide a foundation for a decision support system to manage the sequence of sowings on commercial broccoli farms.
5	Prinos i kvalitet mladog krompira u zavisnosti od agrotehničkih mera i agroekoloških uslova proizvodnje / Yield and quality of early potato dependingTI on agricultural practices and argoecological condicions Vujasinović Vuk 23 September 2016 (has links) <p>Proizvodnja mladog krompira u Srbiji je značajna zbog obezbeđenja ove izuzetno cenjene i delikatesne namirnice u periodu od aprila do juna kada je u ponudi na trži&scaron;tu malo drugog svežeg povrća. Osim toga cena mladog krompira je uglavnom visoka, pa je značaj i po osnovu profitabilnosti ove kulture velik.<br />U periodu 2004-2006. godine ispitivan je efekat malčovanja polietilenskom folijom i<br />neposrednog pokrivanja biljaka sa i bez noseće konstrukcije, kao i kombinacija ovih specifičnih agrotehničkih mera na ranostasnost, prinos i komponente prinosa i kvalitet mladog krompira kod ranih sorti Cleopatra i Riviera. U cilju re&scaron;avanja postavljenog zadatka sprovedeno je istraživanje, na lokalitetu južno bačkog okruga (Begeč), postavljen je dvofaktorijalni ogled po split plot planu u pet ponavljanja.<br />Ispitivane agrotehničke mere i njihove kombinacije značajno su uticale na ranostasnost i prinos mladog krompira. Formiranje trži&scaron;nih krtola (krtole veće od 28 mm) bilo je za 10-15 dana ranije u odnosu na kontrolnu (nepokrivenu) varijantu. Najveći prinos u trogodi&scaron;njem istraživanju postignut je na varijanti agrotekstil+niski tunel (40,07 t/ha). U odnosu na kontrolnu varijantu, prinos je bio veći za 19% (u prvoj godini za 22%, drugoj za 16%, dok je u trećoj godini prinos bio veći za 18%).<br />Najveći broj krtola mladog krompira, u trogodi&scaron;njem istraživanju, ostvaren je na<br />kontrolnoj varijanti (9,43), stim &scaron;to je udeo trži&scaron;nih krtola (krtole veće od 28 mm) na kontroli iznosio 89% naspram 95% ostvaren na pokrivenim varijantama. Riviera je ostvarila veći broj krtola po biljci u odnosu na Cleopatru.<br />Ispitivane agrotehničke mere uticale su na povećanje mase krtola po biljci. Najveća masa krtola po biljci u trogodi&scaron;njem ogledu ostvaren je na tretmanima agrotekstil+niski tunel (853,17 g) i malčovanje+agrotekstil+niski tunel (850,17 g), dok je najmanja masa zabeležena na kontrolnoj varijanti (640 g). Sorta Riviera je ostvarila značajno veću masu krtola u odnosu na Cleopatru.<br />Ispitivani tretmani su ostvarili veću prosečnu masu jedne krtole za 52% u odnosu na<br />kontrolnu varijantu.<br />Ispitivani tretmani značajno su uticali i na kvalitet mladog krompira; odnosno na<br />povećanje sadržaja suve materije, skroba, vitamina C, celuloze i pepela u krtolama, a na<br />smanjenje sadržaja &scaron;ećera i nitrata.</p> / <p>Production of early potato in Republic of Serbia is important because it provides this<br />highly valued delicates food during the period from April to June, when there is low offer of other<br />fresh vegetables on the market. Besides, price of early potato is usually high so it is important as<br />profitable crop.<br />During the period 2004-2006 effect of mulching with polyethylene foil and direct<br />coverage of plants with agrotextile and low tunnel, as well as combinations of these specific<br />agricultural measures on earliness, yield and yield components and quality of two early potato<br />varieties Cleopatra and Riviera was examined. In order to achieve given objective research was<br />conducted at the site in South Bačka District (Begeč), it set up the two-factorial experiment at<br />split plot plan in five replications.<br />The tested of agricultural measures and their combinations significantly influenced<br />earliness and yield of early potato. The forming of market tubers (tubers larger than 28 mm) was<br />10-15 days earlier than on the control variant (bare soil and uncover plants). The highest yield of<br />the three-year study has been made on the variant combination of agrotextile and low tunnel<br />(40,07 t/ha). Compared to the control variant, the yield was increased by 19% (in the first year<br />increase of 22%, second year increase was 16%, while in the third year yield increase was 18%).<br />The largest number of tubers of early potatoes, in three-year study, has been on the<br />control variant (9,43), but the share of market tubers (tubers larger than 28 mm) on the control<br />variant was 89% versus 95% achieved in covered variants. Variety Riviera has achieved greater<br />number of tubers per plant compared to variety Cleopatra.<br />The tested agricultural measures affected mass increase of tubers per plant. The<br />maximum weight of tubers per plant in the three-year experiment was realized in the treatment<br />combination of agrotextile and low tunnel (853,17 g) and combination of mulching, agrotextile<br />and low tunnel (850,17 g), while the lowest mass was recorded in the control variant (640 g).<br />Variety Riviera has achieved significantly higher tuber weight relative to Cleopatra.<br />The tested treatments have also achieved a higher average weight of a tuber of 52%<br />compared to the control variant.<br />The tested treatments significantly influenced quality of early potato; i.e. the increase the<br />content of dry matter, starch, vitamin C, cellulose and ash in the tubers and on reduction of sugar<br />and nitrate content.</p>
6	Заснивање и производно-квалитетне особине еспарзете (Onobrychis viciifolia Scop.) у условима здружене сетве / Zasnivanje i proizvodno-kvalitetne osobine esparzete (Onobrychis viciifolia Scop.) u uslovima združene setve Vujić Svetlana 02 March 2018 (has links) <p>Заснивање вишегодишњих легуминоза у пролећном року сетве често је праћено интензивнијим развојем корова и смањеним приносом. Ово је случај и приликом гајења еспарзете (Onobrychis viciifolia Scop.), која се сматра потенцијалном заменом за луцерку. Здружена сетва, односно гајење две или више врста на једном пољу током одређеног периода, може се користити као начин заснивања ове вишегодишње легуминозе. Осим традиционалног здруживања легуминозе и стрнине, као надусев може се користити и сточни грашак (Pisum sativum L.), због своје краће вегетације и смањеног конкурентског утицаја на подусев. Циљ рада је био да се утврди да ли је сточни грашак погодан за заснивање еспарзете у здруженој сетви, као и да се утврди одговарајућа сорта и густина грашка која омогућава најбољи принос и утицај на подусев. Двофакторијални оглед постављен је на експерименталном пољу Института за ратарство и повртарство, Нови Сад, током 2010-2014. године и укључио је две сорте грашка различитих морфолошких особина (Језеро-афила тип листа, Јавор-редуковане лиске) сејане у три густине. Као контролне варијанте коришћене су чист усев еспарзете и здружена сетва еспарзете и овса. Оглед је засниван у четворогодишњем периоду и испитивања су вршена у години заснивања и првом откосу у години искоришћавања.<br />Утврђено је да су временски услови значајно утицали на остварен принос у току истраживања. Сточни грашак као надусев имао је повољније деловање на еспарзету и њен развој након сваког откоса, с тим да је присуство надусева у другој години живота имало минималан утицај на остварени принос. Принос суве материје у првом откосу био је већи са сортом Језеро. Између приноса са 60 и 90 биљака грашка по m2 разлика у приносу није била статистички значајна, што је посебно значајно са економског аспекта производње. Резултати су показали да је највећи укупан принос суве материје имала еспарзета са овсем, услед значајног са повећањем густине смеше. Резултати су показали да је здружена сетва две легуминозе утицала на већи садржај минералног азота у земљишту након првог откоса. Присуство и густина надусева у првом откосу утицали су на интензивније коришћење влаге у земљишту, док је у наредним мерењима утицај фактора на количину воде у слоју до 60 cm био минималан.</p><p>Значај заснивања еспарзете у здруженој сетви са грашком показан је и кроз садржај сирових протеина, који је био већи у здруженој сетви у односу на чист усев еспарзете. При томе, сварљивост крме је била већа, с обзиром на то да је смеша еспарзете и грашка имала мањи удео NDF-а и ADF-а у односу на контроле.</p><p>Остварени резултати показују да се еспарзета може успешно заснивати у здруженој сетви са сточним грашком чиме се обезбеђује стабилан принос првог откоса високог квалитета, без негативног утицаја на регенерацију еспарзете и принос у наредним откосима. Резултати указују да је здружена сетва поуздан и еколошки начин заснивања еспарзете, који пружа могућност да ова врста буде заступљенија у пракси.удела првог откоса у укупном приносу. Удео корова у здруженој сетви био је мањи у односу на чист усев еспарзете. Сорта Језеро у просеку имала је већу компетативну способност, док је у просеку за обе сорте најмањи удео корова утврђен у смеши са 60 биљака грашка.<br />Морфолошки различите сорте грашка нису довеле до статистички значајних разлика у вредностима индекса лисне површине еспарзете, али се вредност овог параметра смањивала са повећањем густине надусева. Садржај фотосинтетичких пигмената био је већи на третманима са здруженом сетвом, али је и значајно зависио од временских услова. Биолошка активност земљишта била је већа у здруженој сетви у односу на чист усев еспарзете. Бројност азотофиксатора била је већа при мањем присуству надусева, док се укупан број бактерија и гљива<br />повећавао</p> / <p>Zasnivanje višegodišnjih leguminoza u prolećnom roku setve često je praćeno intenzivnijim razvojem korova i smanjenim prinosom. Ovo je slučaj i prilikom gajenja esparzete (Onobrychis viciifolia Scop.), koja se smatra potencijalnom zamenom za lucerku. Združena setva, odnosno gajenje dve ili više vrsta na jednom polju tokom određenog perioda, može se koristiti kao način zasnivanja ove višegodišnje leguminoze. Osim tradicionalnog združivanja leguminoze i strnine, kao nadusev može se koristiti i stočni grašak (Pisum sativum L.), zbog svoje kraće vegetacije i smanjenog konkurentskog uticaja na podusev. Cilj rada je bio da se utvrdi da li je stočni grašak pogodan za zasnivanje esparzete u združenoj setvi, kao i da se utvrdi odgovarajuća sorta i gustina graška koja omogućava najbolji prinos i uticaj na podusev. Dvofaktorijalni ogled postavljen je na eksperimentalnom polju Instituta za ratarstvo i povrtarstvo, Novi Sad, tokom 2010-2014. godine i uključio je dve sorte graška različitih morfoloških osobina (Jezero-afila tip lista, Javor-redukovane liske) sejane u tri gustine. Kao kontrolne varijante korišćene su čist usev esparzete i združena setva esparzete i ovsa. Ogled je zasnivan u četvorogodišnjem periodu i ispitivanja su vršena u godini zasnivanja i prvom otkosu u godini iskorišćavanja.<br />Utvrđeno je da su vremenski uslovi značajno uticali na ostvaren prinos u toku istraživanja. Stočni grašak kao nadusev imao je povoljnije delovanje na esparzetu i njen razvoj nakon svakog otkosa, s tim da je prisustvo naduseva u drugoj godini života imalo minimalan uticaj na ostvareni prinos. Prinos suve materije u prvom otkosu bio je veći sa sortom Jezero. Između prinosa sa 60 i 90 biljaka graška po m2 razlika u prinosu nije bila statistički značajna, što je posebno značajno sa ekonomskog aspekta proizvodnje. Rezultati su pokazali da je najveći ukupan prinos suve materije imala esparzeta sa ovsem, usled značajnog sa povećanjem gustine smeše. Rezultati su pokazali da je združena setva dve leguminoze uticala na veći sadržaj mineralnog azota u zemljištu nakon prvog otkosa. Prisustvo i gustina naduseva u prvom otkosu uticali su na intenzivnije korišćenje vlage u zemljištu, dok je u narednim merenjima uticaj faktora na količinu vode u sloju do 60 cm bio minimalan.</p><p>Značaj zasnivanja esparzete u združenoj setvi sa graškom pokazan je i kroz sadržaj sirovih proteina, koji je bio veći u združenoj setvi u odnosu na čist usev esparzete. Pri tome, svarljivost krme je bila veća, s obzirom na to da je smeša esparzete i graška imala manji udeo NDF-a i ADF-a u odnosu na kontrole.</p><p>Ostvareni rezultati pokazuju da se esparzeta može uspešno zasnivati u združenoj setvi sa stočnim graškom čime se obezbeđuje stabilan prinos prvog otkosa visokog kvaliteta, bez negativnog uticaja na regeneraciju esparzete i prinos u narednim otkosima. Rezultati ukazuju da je združena setva pouzdan i ekološki način zasnivanja esparzete, koji pruža mogućnost da ova vrsta bude zastupljenija u praksi.udela prvog otkosa u ukupnom prinosu. Udeo korova u združenoj setvi bio je manji u odnosu na čist usev esparzete. Sorta Jezero u proseku imala je veću kompetativnu sposobnost, dok je u proseku za obe sorte najmanji udeo korova utvrđen u smeši sa 60 biljaka graška.<br />Morfološki različite sorte graška nisu dovele do statistički značajnih razlika u vrednostima indeksa lisne površine esparzete, ali se vrednost ovog parametra smanjivala sa povećanjem gustine naduseva. Sadržaj fotosintetičkih pigmenata bio je veći na tretmanima sa združenom setvom, ali je i značajno zavisio od vremenskih uslova. Biološka aktivnost zemljišta bila je veća u združenoj setvi u odnosu na čist usev esparzete. Brojnost azotofiksatora bila je veća pri manjem prisustvu naduseva, dok se ukupan broj bakterija i gljiva<br />povećavao</p> / <p>The establishment of perennial legumes in the spring is often followed by intensive weeds infestation and reduced yield. This is also the case when growing sainfoin (Onobrychis viciifolia Scop.) which is considered a potential substitute for alfalfa (Medicago sativa L.). Intercropping or growing two or more species in the same field during a certain period can be used for establishing this perennial legume. A field pea (Pisum sativum L.) has a potential to be used as companion crop due to a short growing season and reduced competing impact. The aim of this research was to determine the suitability of field pea as a companion crop for sainfoin establishment and to determine the appropriate cultivar and pea density that provides the best yield and impact on undersown crop. A two-factorial trial was set up in the experimental field of the Institute of Field and Vegetable Crops, Novi Sad, during 2010-2014. The experiment included two morphologically different pea cultivars (Jezero-afila leaf type and Javor-reduced leaflet) and three pea densities. The sainfoin pure stand and a mixture with oat were used as control treatments. The trial included four sowing years and the analysis was performed in the establishment years and in the first cut in the full harvest year.<br />The weather conditions significantly influenced obtained yield. Field pea as a companion crop had a better impact on sainfoin development in the establishment year, while in subsequent year companion crops had minimal impact on sainfoin yield. Concerning pea cultivars, a higher dry matter yield was obtained with cultivar Jezero. It was concluded, there were no significant differences between obtained yield with 60 and 90 pea plants per m2 which have importance from the economic aspect. The results showed that the highest annual yield had a mixture of sainfoin and oat, due to a significant share of the first yield. The weed proportion was lower in intercropping compared to the sainfoin pure stand. The cultivar Jezero and a density of 60 pea plants per m2 were more competitive to weeds.<br />Morphologically different pea cultivars did not significantly affect leaf area index of sainfoin. However, its value decreased with the increase of pea density in the stand. Intercropping and weather conditions had a significant impact on pigment content in sainfoin leaves. The examined soil biological activity was higher in intercropping treatments. The number of nitrogen fixation bacteria increased with a decreased number of pea plants, while the number of total bacteria and fungi increased with increasing pea density. The intercropping of the legumes influenced the higher content of mineral nitrogen in the soil, but also the more intensify use of soil moisture. The positive effect of intercropping of two legumes was demonstrated by the obtained higher content of crude protein with a lower proportion of digestibility parameters - NDF and ADF compared to both control treatments.<br />The obtained results show that sainfoin can be successfully established with field pea in intercropping, which ensures the stable and high-quality yield of the first cut, without negative esainfoin re-growth and yield in subsequent cuts. Thus, intercropping can be considered as a reliable and ecological practice for sainfoin establishment, which provides the possibility for increasing production of this species.</p>
7	Nutrição mineral, produção, qualidade e análise econômica do abacaxizeiro cv. Pérola, em função das relações K/N / Mineral nutrition, yield, quality and economical analysis of the pineapple plant Pérola cv. as a function of the K/N relationships Rodrigues, Alessandra Alves 29 May 2009 (has links) Submitted by Katiane Souza (katyane.souza@gmail.com) on 2016-05-18T00:13:41Z No. of bitstreams: 1 arquivototal.pdf: 2616061 bytes, checksum: c0e8a719c2c62222df7369e721a7caac (MD5) / Made available in DSpace on 2016-05-18T00:13:41Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2616061 bytes, checksum: c0e8a719c2c62222df7369e721a7caac (MD5) Previous issue date: 2009-05-29 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The management of the pineapple plant fertilization requires the applications of N and K at high doses, besides the establishment of appropriate relationships among them. This study was conducted to evaluate the effect of the different K/N relationships on the mineral nutrition, yield and quality of the pineapple fruits 'Pérola'. The experiment was carried out in a low fertile and sandy-textured Espodossolo Ferrocárbico at Santa Rita county of Paraíba State, during the period from March 2006 to September 2007. The randomized block experimental design was adopted, with three replicates. The slip type suckers were planted at spacing 0.80 × 0.30 m under simple row system. Thirteen treatments resulting from four relationships K/N (0.85:1; 1:1; 2:1 and 3:1) generated from two N doses, as being one considered low (7.2 g/plant N) and another high (10.8 g/plant N) were evaluated. Other four additional treatments (source, plotting, time and the application form of the potassium fertilizer) and control (without fertilization). At 0-20cm depth of the soil, the following variables were determined: pH and contents of the organic matter, P, K, Ca, Mg and Al. At 120, 240 and 330 days after planting, the leaf contents of N, P, K, Ca, Mg and S were determined and the values of the relationships K/N, K/Ca and K/Mg were estimated. The harvest was accomplished at 17 months after planting and the following variables were evaluated: average weight of the fruits, total productivity and percent fruits of the classes I (0.8-1.2 kg), II (1.20- 1.50 kg) and III (1.51-1.80 kg). Concerning to quality, the following characteristics were determined in the fruits pertaining to classes I and II: length and average diameter; length and weight of the crown; weights of the husk, of the pulp and of the stem; pH, soluble solids (obrix), titrable acidity and relationship SS/AT . The evaluation of the economical viability of the treatments were based on the cost/benefit relationship (C/B). The results showed that the K/N relationships and the additional treatments did not affect the attributes of soil fertility, except for the contents of K and S. The K/N relationships did not affect the weight of the 'D' leaf neither the leaf contents of N, P, K, Ca and Mg in the samplings accomplished at four, eight months and at the floral induction time. They also did not affect the average weight, the productivity and the percent fruits pertaining to classes I, II and III. Higher N doses (450 kg/ha) increased the average weight, total productivity and the percent fruits of the classes II and III, but reduced the percent fruits of the class I. The K sulfate increased either average weight and percent fruits of the class III, whereas the N and K doses from which half was applied on the soil and half through leaf rather increased the productivity of fruits. The K/N relationships did not affect the quality attributes of the fruits, although the N and K applications after floral induction and that of K sulfate reduced the acidity of the fruits. The use of the K sulfate resulted into higher gross revenue and higher additional value, although the highest B/C relationship was obtained with the application of half doses on the soil and half ones via leaf (R$ 1,46). / O manejo da adubação do abacaxizeiro requer além de aplicações de doses elevadas de N e K, o estabelecimento de relações adequadas entre estas. O objetivo deste trabalho foi o avaliar o efeito de diferentes relações K/N sobre a nutrição mineral, produção e a qualidade dos frutos de abacaxi ‘Pérola’. O experimento foi conduzido em Espodossolo Ferrocárbico de textura arenosa e de baixa fertilidade do município de Santa Rita, estado da Paraíba, entre março de 2006 e setembro de 2007. Adotou-se o delineamento experimental de blocos casualizados, com três repetições, utilizandose mudas do tipo filhote, plantadas em sistema de fileiras simples, no espaçamento de 0,80 × 0,30 m. Foram avaliados 13 tratamentos, resultantes de quatro relações K/N (0,85:1; 1:1; 2:1 e 3:1), geradas a partir de duas doses de N, uma considerada baixa (7,2 g/planta de N) e outra alta (10,8 g/planta de N), acrescidos de quatro tratamentos adicionais (fonte, parcelamento, época e forma de aplicação do fertilizante potássico) e uma testemunha absoluta (sem adubação). No solo foram determinados, na profundidade de 0-20 cm, pH e teores de matéria orgânica, P, K, Ca, Mg e Al. Foram avaliados aos 120, 240 e 330 dias após o plantio os teores foliares de N, P, K, Ca, Mg e S, e em seguida estimados os valores das relações K/N, K/Ca e K/Mg. Na colheita, realizada aos 17 meses após o plantio foram avaliadas as seguintes variáveis: peso médio dos frutos, produtividade total e percentual de frutos das classes I (0,8-1,2 kg), II (1,20-1,50 kg) e III (1,51-1,80 kg). Em relação à qualidade foram determinadas nos frutos das classes I e II as seguintes características: comprimento e diâmetro mediano; comprimento e peso da coroa; peso da casca, da polpa e do talo; pH, sólidos solúveis (obrix), acidez titulável e relação SS/AT. A viabilidade econômica dos tratamentos foi avaliada por meio da relação Benefício/Custo (B/C). Os resultados obtidos mostraram que as relações K/N e os tratamentos adicionais, com exceção dos teores de K e de S, não afetaram os atributos de fertilidade do solo. As relações K/N não afetaram o peso da folha ‘D’ e os teores foliares de N, P, K, Ca e Mg em amostragens feitas aos quatro, oito meses e na época de indução floral. Não influenciaram também o peso médio, a produtividade e o percentual de frutos das classes I, II e III. Doses mais elevadas de N (450 kg/ha) aumentaram o peso médio, a produtividade total, e os percentuais de frutos das classes II e III, e reduziram o percentual de frutos da classe I. A utilização de sulfato de K aumentou o peso médio e o percentual de frutos da classe III, enquanto que doses de N e K aplicadas metade no solo e metade via foliar aumentaram a produtividade de frutos. As relações K/N não influenciaram os atributos de qualidade dos frutos, embora aplicações de N e K após a indução floral e de sulfato de K diminuíram a acidez dos frutos. A utilização de sulfato de K resultou em maior receita bruta e maior valor adicional, embora a maior relação B/C foi obtida com a aplicação das doses metade no solo e metade via foliar (R$ 1,46). Ananas comosus comosus Adubação mineral Interação N × K Análise econômica Qualidade da produção Fertilization Yield quality Interaction N × K Economical analysis Ananas comosus comosus CIENCIAS AGRARIAS::AGRONOMIA
8	Birds, bats and arthropods in tropical agroforestry landscapes: Functional diversity, multitrophic interactions and crop yield Maas, Bea 20 November 2013 (has links) No description available. 630 birds bats arthropods multitrophic interactions agroforestry tropical landscape forest margin landscape functional diversity crop yield exclosure experiments experimental exclusion arthropod suppression avian predation ecosystem services mist netting point counts artificial plasticine caterpillar dummy experiment biological control monitoring mapping Lemon-bellied White-eye Grosbeak Starling Zosterops chloris Scissiostrum dubium Theobroma cacao cacao agroforestry cacao diseases cacao harvest cacao pests flying vertebrates aerial insectivores volant vertebrates logging breeding colony flower herbivory mesopredator release predatory insects ants spiders aphids Lepidoptera Coleoptera Lepidopteran larvae sustainable agriculture sustainable agroforestry management implications management recommendations applied managament extensive land use management landscape management conservation biodiversity-friendly dbh distance to forest forest proximity habitat conversion herbivory Indonesia insectivorous bats insectivorous birds invertebrates Central Sulawesi Napu valley leaf gleaning leaf herbivory pests insects phytophagous insects plant productivity remnant forest trees shade tree managament South-east Asia Paleotropics tropical landscape tree height landscape gradient local shade management Cacao Pod Borer Cherelle Wilt fruit abortion Helopeltis sulawesi deforestation habitat fragmentation land use intensification forest margin species critical decline predation experiment species-specific functions Southeast Asia biodiversity conservation mesopredators food security human welfare human well-being poverty alleviation poverty reduction smallholder cacao smallholder plantation cacao farmers sustainable cacao management landscape perspective landscape scale large scale field experiment long term field experiment human wellbeing economic importance economic value valuation ecosystem services landscape matrix yield quality yield quantity fruit productivity species identity species diversity species richness ecosystem functioning pesticide use chemical compounds complex food web tritrophic interactions wildlife-friendly rural livelihoods endangered bird species endangered bat species endemic endemic birds endemic bats beneficial impact IUCN Lore Lindu National Park bioindicator indicator species forest margin agricultural habitat agroforestry systems population density predation activity species activity cacao flower cacao pod Orthoptera linear mixed effect models Tukey Post Hoc Test AICc model selection generalized least squares restricted maximum likelihood model simplification species richness estimator species accumulation linear mixed-effects models Likelihood Ratio Test Maximum Likelihood nocturnal insects diurnal arthropods nocturnal arthropods diurnal insects landscape context Land- und Forstwirtschaft (PPN621302791)

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