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Effects of defoliation on the cultivated strawberry (Fragaria X ananassa Duch.)Kerkhoff, Karen Leigh 17 November 2012 (has links)
Using 'Redchief' (Junebearer) and 'Tribute' (dayneutral) cultivars, greenhouse and field studies were conducted to determine the effects of defoliation on photosynthesis, growth and yield of the strawberry. From preliminary photosynthesis experiments it was found that both 'Redchief' and 'Tribute' strawberry leaves reached maximum net photosynthesis (Pn) concurrently with full leaf expansion at approximately 8 to l0 days and 4 to 5 days, respectively, after unfolding. By exposing the plants to increasing irradiance it was determined that these cultivars were light saturated at 600 to 700)Ï molâ ¢m⁻²s⁻¹. Neither cultivar showed a consistent diurnal pattern when Pn was monitored hourly over two consecutive days. / Master of Science
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Estratégias de utilização do capim-andropógon / Strategies for the use of andropogongrassCosta, Clésio dos Santos 14 February 2017 (has links)
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Previous issue date: 2017-02-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico e Tecnológico do Maranhão (FAPEMA) / The grass-andropogon is a perennial grass is well resistant to low fertility soils, to places that suffer water restriction as in the Northeast region. The objective of this study was to evaluate strategies for the use of andropogongrass during the rainy season. The structural and chemical characteristics were evaluated as a function of two defoliation intensities and rest periods. In the dry period the nutritive value of deferred andropogenic grass treated with ammonia. Experiment rains: two defoliation intensities (15 and 30 cm) and four rest periods (25, 35, 45 and 55 days) were evaluated in a completely randomized design in a factorial arrangement, with four replications. Depletion intensity did not affect dry leaf biomass (P> 0.05). The rest period provided a linear decreasing effect (P <0.05) on the biomass of dried leaf blades in the two defoliation intensities. It was observed that the intensity of 15 cm occurred a reduction of 19.52 kg of leaves for each day of rest, already in the intensity of 30 cm was registered a reduction of 35.41 kg for each day. The biomass of dry stalks showed an increasing linear effect (P <0.05) as a function of the rest periods in the two defoliation intensities. Production of 2427.71, 2907.39, 3325.72 and 3749.45 kg ha-1 was recorded for the periods of 25, 35, 45 and 55 days respectively. In the intensity of 30 cm, a reduction of 40.75 kg was recorded for each day of rest period. The rest period provided a linear decreasing effect (P <0.05) on the blade / stem ratio in the two defoliation intensities. A reduction of 0.02 and 0.03 was observed for each day of the rest period in intensities of 15 and 30 cm, respectively, the highest relation was observed with 25 days (1.39) and the lowest with 55 days (0. 64). The population density of tillers responded in a linear descending manner (P> 0.05) to the rest periods for the defoliation intensity of 15 cm, with a reduction of 2.59 tillers for each day over a rest period. For the intensity of 30 cm, no linear regression effect was observed (Y = 530.10). The height of the pasture was influenced by the rest periods, with values of 1.33, 1.82, 2.07 and 2.24 m recorded for the periods of 25, 35, 45 and 55 days respectively. The DM content presented an increasing linear effect (P <0.05) as a function of the rest periods evaluated in the two defoliation
intensities. For each additional day in the rest period, an increase of 2.8 and 2.7 g / kg was recorded for the intensities of 15 and 30 cm, respectively. The rest period indicated a linear decreasing behavior (P <0.05) for PB content in the two defoliation intensities. A decrease of 0.9 and 0.7 g / kg was recorded for each day of rest period. For each day over the rest period an increase of 1.2 and 1.5 g / kg DM in the NDF content was recorded at intensities of 15 and 30
cm. It is recommended the use of managed andropogon grass with regrowth age of 25 days and height of residue of 15 cm. Dry experiment: For the chemical composition, a completely randomized design was used, with five treatments (0, 2, 4, 6, and 8% addition of urea in% of DM) and five replications. To evaluate the in situ degradation of DM, a fistulated sheep with a mean live weight of 60 kg was used. For the degradation, a completely randomized design was
used in a 5 x 4 factorial arrangement (five urea levels x four incubation times 6, 24, 48 and 72). The ammonization provided a linear effect (P <0.05) for the DM content of the andropogon grass, a minimum level of 4.63 urea was recorded, and from this level the MS content increased again. There was a positive linear effect (P <0.05) for the crude protein (CP) contents, an increase of 15.07 g / kg of PB was observed for each 1% of urea added to the andropogon grass, the value of Protein obtained through the equation for the highest dose was 139.4 g / kg DM. The effect of ammonia on neutral detergent fiber (NDF), hemicellulose and acid detergent fiber (ADF) was observed, respectively, with a decrease of 10.45, 4.06 and 6.39 g / kg of DM respectively. The neutral detergent insoluble nitrogen content (NIDN) was negatively linear (P <0.05) as a function of ammonia. It was recorded that for each 1% of urea a reduction of 41.77 g / kg was observed. However, ash content did not show any effect (P> 0.05), values of 27.0, 31.8, 32.0, 36.1 and 36.6 g / kg DM were recorded at levels of 0, 2, 4, 6 and 8%, respectively. The soluble fraction of the andropogon grass increased as the ammonia levels increased (14.20, 16.19, 17.27, 19.23, 18.04%, to the levels of 0, 2, 4, 6 And 8%, respectively). It is recommended to use the addition of urea at the 4% level in the process of ammonization of the deferred andropgrass grass. / O capim-andropogon é uma gramínea perene é bem resistente a solos de baixa fertilidade, a locais que sofrem restrição hídrica como na região Nordeste. Diante disso, objetivou-se avaliar estratégias de utilização do capim-andropógon, no período das chuvas, avaliou-se as características estruturais e químicas em função de duas intensidades de desfolha e períodos de descanso. No período seco avaliou-se o valor nutritivo do capim-andropogon diferido e tratado com amonização. Experimento chuvas: foram avaliadas duas intensidades de desfolha (15 e 30 cm) e quatro períodos de descanso (25, 35, 45 e 55 dias) em delineamento inteiramente casualizado em arranjo fatorial, com quatro repetições. A intensidade de desfolha não afetou (P>0,05) a biomassa de lamina foliar seca. O período de descanso proporcionou efeito linear decrescente (P<0,05) sobre a biomassa de lâminas foliares secas nas duas intensidades de desfolha. Foi observado que na intensidade de 15 cm ocorreu uma redução de 19,52 kg de folhas para cada dia de descanso, já na intensidade de 30 cm foi registrado uma redução de 35,41 kg para cada dia. A biomassa de colmos secos apresentou efeito linear crescente (P<0,05) em função dos períodos de descanso nas duas intensidades de desfolha. Foi registrado produção de 2427,71, 2907,39, 3325,72 e 3749,45 kg ha-1 para os períodos de 25, 35 45 e 55 dias, respectivamente. Já na intensidade de 30 cm foi registrado redução de 40,75 kg para cada dia de período de descanso. O período de descanso proporcionou efeito linear decrescente (P<0,05) sobre a relação lâmina/colmo nas duas intensidades de desfolha. Foi observado redução de 0,02 e 0,03 para cada dia do período de descanso nas intensidades de 15 e 30 cm, respectivamente, a maior relação foi observada com 25 dias (1,39) e a menor com 55 dias (0,64). A densidade populacional de perfilhos respondeu de forma linear decrescente (P>0,05) aos períodos de descanso para a intensidade de desfolha de 15 cm, sendo registrado uma redução de 2,59 perfilhos para cada dia a mais de período de descanso. Já para a intensidade de 30 cm não foi observado efeito de regressão linear (Y=530,10). A altura do pasto foi influenciada pelos períodos de descanso, sendo registrado valores de 1,33, 1,82, 2,07 e 2,24 m, para os períodos de 25, 35, 45 e 55 dias, respectivamente. O teor de MS apresentou efeito linear crescente (P<0,05) em função dos períodos de descanso avaliados nas duas intensidades de desfolha. Para cada dia a mais no período de descanso, foi registrado aumento de 2,8 e 2,7 g/kg para as intensidades de 15 e 30 cm, respectivamente. O período de descanso indicou comportamento linear decrescente (P<0,05) para o teor de PB nas duas intensidades de desfolha. Foi registrado uma diminuição de 0,9 e 0,7 g/kg para cada dia de período de descanso. Para cada dia a mais de período de descanso foi registrado aumento de 1,2 e 1,5 g/kg de MS no teor de FDN nas intensidades de 15 e 30 cm. Recomenda-se o uso do capim-andropógon manejado com idade de rebrotação de 25 dias e altura de resíduo de 15 cm. Experimento seca: Para composição química, adotou-se o delineamento inteiramente casualizado, com cinco tratamentos (0, 2, 4, 6, e 8 % de adição de ureia, em % da MS) e cinco repetições. Para avaliação da degradação in situ da MS, foi utilizado um ovino fistulado com peso vivo médio de 60 kg. Para degradação adotou-se o delineamento inteiramente casualizado em arranjo fatorial 5 x 4 (cinco níveis de ureia x quatro tempos de incubação 6, 24, 48 e 72). A amonização proporcionou efeito linear (P<0,05) para o teor de MS do capim-andropógon, foi registrado nível mínimo de 4,63 de ureia, sendo que, a partir deste nível o teor de MS volta a subir. Verificou-se efeito linear positivo (P<0,05) para os teores de proteína bruta (PB), foi observado aumento de 15,07 g/kg de PB para cada 1% de ureia adicionado ao capim-andropógon, o valor de proteína obtido através da equação para a maior dose foi de 139,4 g/kg de MS. Também foi observado efeito da amonização sobre os teores de fibra em detergente neutro (FDN), hemicelulose e fibra em detergente ácido (FDA), foi registrado redução de 10,45, 4,06 e 6,39 g/kg de MS, respectivamente. O teor de nitrogênio insolúvel em detergente neutro (NIDN), sofreu efeito linear negativo (P<0,05) em função da amonização. Foi registrado que para cada 1% de ureia foi observado redução de 41,77 g/kg. Já o teor de cinzas não sofreu efeito (P>0,05), foi registrado valores de 27,0, 31,8, 32,0, 36,1 e 36,6 g/kg de MS para os níveis de 0, 2, 4, 6 e 8%, respectivamente. A fração solúvel do capim-andropógon aumentou à medida que se elevou os níveis de amonização (14,20, 16,19, 17,27, 19,23, 18,04 %, para os níveis de 0, 2, 4, 6 e 8%, respectivamente). Recomenda-se utilizar a adição de ureia no nível de 4 % de no processo de amonização do capim-andropógon diferido.
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Dinâmica de desfolhação em pastos de capim-quicuiu manejados em lotação intermitente / Dynamics of defoliation in kikuyu grass pastures under intermittent stockingMedeiros Neto, Cauby de 24 February 2015 (has links)
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Previous issue date: 2015-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Recent studies have shown that, in rotational stocking, post- grazing target should not exceed 40% of severity of defoliation of pre-grazing height. Although there is some evidence that from that level of defoliation animals start to graze undesirable horizons, there is not such evidence how these processes occurs at plant level. Thus, the aim of this study was to evaluate the dynamics of defoliation during the grazing down of kikuyu grass pastures (Pennisetum clandestinum Hochst. Ex. Chiov.), testing the hypothesis that the transition between the grazing horizons occurs when animals defoliate around 40% of initial height. The experiment was conducted using a pre-grazing height of 25 cm combined with levels of defoliation of 40, 50, 60 and 70% of the initial height. The experimental design was a randomized complete block with four treatments and three replications. Pastures were grazed down in 24 hours and assessments related to the dynamics of defoliation were conducted in four times during this period of occupation by using marked tillers technique. Were evaluated aspects of the frequency and intensity of defoliation by leaf category, tiller, extended tiller and stem, and the total grazed area, grazed area only once, grazed area two to three times and total regrazed area. It was found that the frequency of defoliation of individual tiller increased linearly with the stocking density and the technique of extended tiller underestimate the magnitude of frequency of defoliation regardless of severity of defoliation. From 40% of severity of defoliation, the probability of defoliation of senescent leaves and stems increased from two to three times, respectively. Both leaf and extended tiller were grazed, on average, with a relatively constant intensity. The transition between grazing horizons begins before 40% of severity of defoliation and to this severity is inevitable that approximately
25% of the grazed area suffer a second or third defoliation. It was concluded that, from the 40% of severity of defoliation, the exploration of lower horizons exceed the limit of 25% of the previously grazed area / Estudos recentes têm mostrado que, em lotação intermitente, a meta pós-pastejo não deve exceder 40% de rebaixamento da altura inicial dos pastos. Apesar de existirem indícios de que a partir dessa severidade de desfolhação os animais passam a pastejar horizontes indesejáveis, não existem evidências em nível de planta de como esses processos ocorrem. É por esse motivo que o objetivo deste trabalho foi avaliar a dinâmica de desfolhação durante o rebaixamento de pastos de capim-quicuiu (Pennisetum clandestinum Hochst. Ex. Chiov.), testando a hipótese de que a transição entre os horizontes de pastejo ocorre quando os animais desfolham em torno de 40% da altura em pré-pastejo. O experimento foi realizado utilizando uma altura em pré-pastejo de 25 cm combinada com severidades de desfolhação de 40, 50, 60 e 70% em relação à altura inicial. O delineamento experimental adotado foi de blocos completos casualizados com quatro tratamentos e três repetições. Cada pasto foi ocupado pelos animais por um período 24 horas e as avaliações referentes à dinâmica de desfolhação foram realizadas em quatro momentos durante esse período de ocupação por meio da técnica de perfilhos marcados. Foram avaliados aspectos relativos à frequência e intensidade de desfolhação por categoria de folha, perfilho, perfilho estendido e colmo, além da área pastejada total, área pastejada apenas uma, duas e três vezes e área repastejada total. Verificou-se que a frequência de desfolhação do perfilho individual aumentou linearmente com a densidade de lotação e que a técnica do perfilho estendido subestima a magnitude da frequência de desfolhação independente da severidade de desfolhação. A partir de 40% de severidade de desfolhação a ingestão de folhas senescentes e de colmos aumentou de duas a três vezes, respectivamente. Tanto as folhas como o perfilho estendido foram pastejados, em média, com uma intensidade relativamente constante. A transição entre horizontes de pastejo se inicia antes de 40% de rebaixamento dos pastos e até esta severidade de
desfolhação é inevitável que aproximadamente 25% da área pastejada sofra uma segunda ou terceira desfolhação. É possível concluir que, a partir da severidade de 40% de desfolhação, a exploração de horizontes inferiores ultrapassa o limite de 25% da área previamente pastejada
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Physiological implications of partial defoliation of the grapevine (Vitis vinifera L. cv. Cabernet Sauvignon)Hunter, Jacobus Johannes 03 1900 (has links)
Thesis (PhD) -- Stellenbosch University, 1991. / ENGLISH ABSTRACT: The effect of partial defoliation as canopy management practice on metabolism and grape
composition of the grapevine, Vitis vinifera L cv. Cabernet Sauvignon, was investigated. The
establishment of physiologically sound principles on how to overcome deleterious effects
associated with vigorous and dense-canopy vines is emphasized. Experimental vines were
defoliated 33 % and 66 % evenly over the whole canopy from different developmental stages in
a field study. Effects on canopy microclimate, photosynthesis, photosynthate translocation,
vegetative growth, reproductive growth, root development and distribution, as well as grape and
wine quality, were determined. A method for the simultaneous extraction of sugars and organic
acids from freeze-dried berries at different developmental stages is described.
Partial defoliation of vines improved canopy microclimate and photosynthetic efficiency of
remaining leaves. Normal translocation and distribution patterns of photosynthates were
apparently unaffected by partial defoliation. Translocation to and accumulation of photosynthetic
products in the leaves and bunches of partially defoliated vines were, however, improved.
Remaining leaves of partially defoliated vines were in comparison photosynthetically more active.
Apart from a less favourable canopy microclimate, it seemed that the sink capacity of
non-defoliated vines did not comply to the source capacity, inducing a reduced rate of
photosynthesis.
Normal sigmoidal growth patterns of vines were not affected by partial defoliation as applied in
this study. This is important for the longevity, healthiness and productivity of vines. Vegetative
growth was differentially affected by partial defoliation. No compensatory leaf growth occurred in
reaction to partial defoliation from different developmental stages. Main shoot length, however,
decreased slightly. Lateral shoot length and number of laterals increased, whereas cane mass
decreased when vines were partially defoliated, particularly the earlier and more severe the
defoliation. Reproductive growth in terms of yield was deleteriously affected by 33 % defoliation
prior to pea size and 66 % defoliation prior to veraison. Budding percentage was, however,
improved by 33 % and 66 % defoliation, whereas bud fertility was only improved by 33 %
defoliation. Partial defoliation changed the canopy microclimate to conditions favourable for pest
and disease control and higher grape quality.
Subterranean growth was favourably affected by partial defoliation, particularly when applied from
pea size stage. These changes included higher root densities, development of higher numbers
of fine and medium diameter roots and occurrence of higher total root numbers in all soil layers.
Generally, defoliations from pea size and veraison were more efficient regarding root
development than defoliations from just after bud break and from berry set. Partially defoliated vines reacted by forming new roots, creating a more efficient nutrient absorption capacity and
utilization of soil and available water and that, together with higher photosynthetic activities of
leaves, provided an efficient mechanism for continued high performance.
Grape quality was not affected markedly by partial defoliation. Total soluble solids in berries of
defoliated vines were comparable to and even significantly higher than those of non-defoliated
vines in some cases, in spite of much lower leaf areas. Generally, total titratable acidity of musts
was also slightly higher for partially defoliated vines. Glucose and fructose concentrations in
berries were unaffected by partial defoliation, while tartaric acid concentrations were slightly
increased and malic acid concentrations slightly decreased. Partial defoliation generally
increased the anthocyanin concentration of berry skins. These changes in grape composition
suggest higher grape quality and seemed to result from improved light conditions in the canopy
interior. Berry volume decreased with partial defoliation, which lowered the pulp:skin ratio.
These berries are more desirable for quality wines. Regardless of severity or the developmental
stage defoliation was commenced, wine cultivar character and overall wine quality were
significantly improved.
Partial defoliation changed the general metabolism of vines, mainly in terms of more favourable
source:sink ratios, resulting in more efficient photosynthesis, subterranean performance and
canopy microclimate. In general, the results suggest that an even removal of 33 % of leaves
opposite and below bunches during the period from flowering or berry set to pea size stage may
be applied. lt is further suggested that existing vigorous and dense-canopy vines be 33 %
defoliated evenly on the lower half of the shoot (canopy) from pea size or veraison. This
hypothesis proved effective in improving canopy microclimate, photosynthetic activity and yield,
while vegetative growth was inhibited. Grape and wine quality were higher.
On the whole, partial defoliation as applied in this study, is recommended as canopy
management practice in order to facilitate the abolishment of deleterious effects of excessive
vegetative growth and canopy density on balanced metabolic activity, fruit and wine quantity and
quality, as well as longevity and healthiness of grapevines. / AFRIKAANSE OPSOMMING: Die invloed van blaarverwydering as loofbestuurspraktyk op die metabolisme en
druifsamestelling van die wingerdstok, Vitis vinifera L cv. Cabernet Sauvignon, is ondersoek. Die
vestiging van fisiologies-betroubare beginsels oor hoe nadelige effekte geassosieerd met geil en
lower-verdigte wingerde uitgeskakel kan word, word beklemtoon. Proefstokke is in 'n
veldondersoek 33 % en 66 % eweredig oor die hele lower vanaf verskillende
ontwikkelingstadiums ontblaar. Effekte op lowermikroklimaat, fotosintese, translokasie van
fotosintetiese produkte, vegetatiewe groei, reproduktiewe groei, wortelontwikkeling en
verspreiding asook druif- en wynkwaliteit is bepaal. 'n Metode vir die gelyktydige ekstraksie van
suikers en organiese sure uit gevriesdroogde korrels op verskillende groeistadiums is ontwikkel.
Blaarverwydering het lowermikroklimaat verbeter en fotosintetiese doeltreffendheid van
oorblywende blare op die stok verhoog. Normale translokasie en verspreidingspatrone van
produkte van fotosintese is skynbaar nie deur blaarverwydering befiwloed nie. Translokasie na,
en akkumulering van fotosintetiese produkte in die blare en druiwe van gedeeltelik ontblaarde
stokke, is egter verbeter. Oorblywende blare van gedeeltelik ontblaarde stokke was fotosinteties
meer aktief. Afgesien van 'n ongunstiger lowermikroklimaat, het die sinkkapasiteit van
nie-ontblaarde stokke skynbaar ook nie teen die bronkapasiteit opgeweeg nie en is 'n verlaagde
tempo van fotosintese verkry.
Normale sigmofdale groeipatrone van die stokke is nie deur blaarverwydering befrivloed nie. Dit
is belangrik vir langlewendheid, gesondheid en produktiwiteit van stokke. Vegetatiewe groei is
differensieel deur blaarverwydering befrivloed. Geen kompenserende blaargroei het in reaksie
op blaarverwydering vanaf verskillende ontwikkelingstadiums voorgekom nie. Hooflootlengte
was egter effens korter. Sylootlengte en aantal sylote het toegeneem, terwyl lootmassa
afgeneem het met blaarverwydering, veral hoe vroeer en strawwer dit toegepas is.
Reproduktiewe groei in terme van opbrengs is nadelig befrivloed deur 33 % ontblaring voor
ertjiekorrelstadium en 66 % ontblaring voor die deurslaanstadium. Botpersentasie is egter deur
blaarverwydering verbeter, terwyl oogvrugbaarheid slegs deur 33 % ontblaring verbeter is.
Blaarverwydering het 'n gunstige lowermikroklimaat vir die beheer van plae en siektes en hoer
druifkwaliteit geskep.
Ondergrondse groei is gunstig deur blaarverwydering befrivloed, veral wanneer toegepas vanaf
ertjiekorrelstadium. Hierdie veranderinge het ingesluit hoer worteldigtheid, ontwikkeling van
groter hoeveelhede wortels met 'n fyn en medium deursnit en die voorkoms van 'n groter aantal
totale wortels in alle grondlae. Blaarverwydering vanaf ertjiekorrel- en deurslaanstadia was in die algemeen meer doeltreffend ten opsigte van wortelontwikkeling as blaarverwydering vanaf net
na bot en vanaf korrelset. Gedeeltelik ontblaarde stokke het gereageer deur nuwe wortels te
vorm, waardeur 'n meer doeltreffende vermoe tot voedingstofopname en benutting van grand an
beskikbare water verkry is. Tesame met hoer fotosintetiese aktiwiteite van die blare is 'n
doeltreffende meganisme vir aanhoudende hoe prestasie verkry.
Druifkwaliteit is nie aanmerklik deur blaarverwydering beirwloed nie. Totale oplosbare stowwe in
druiwe van gedeeltelik ontblaarde stokke was vergelykbaar en selfs betekenisvol hoer as die van
nie-ontblaarde stokke in sekere gevalle, ten spyte van die baie laer blaaroppervlakte. In die
algemeen was die totale titreerbare suur in die mos van gedeeltelik ontblaarde stokke oak effens
hoer. Glukose- en fruktosekonsentrasies in die druiwe is nie deur blaarverwydering beinvloed
nie. Die konsentrasie wynsteensuur is egter effens verhoog en die appelsuurkonsentrasie effens
verlaag. Antosianienkonsentrasie van korreldoppe is in die algemeen deur blaarverwydering
verhoog. Hierdie veranderinge in druifsamestelling dui op hoer druifkwaliteit en is skynbaar die
resultaat van verbeterde ligtoestande in die binnekant van die lower. Korrelvolume het
afgeneem met blaarverwydering. Dit het die pulp:dop verhouding verlaag. Sulke korrels is meer
gewens vir bereiding van kwaliteitswyne. Wyn cultivarkarakter en totale wynkwaliteit is
betekenisvol deur blaarverwydering verhoog, onafhanklik van die strafheid of
ontwikkelingstadium waarvandaan blare verwyder is.
Blaarverwydering het die algemene metabolisme van die wingerdstok verander, hoofsaaklik ten
opsigte van meer gunstige bron:sink-verhoudings en derhalwe meer doeltreffende fotosintese,
ondergrondse groei en lowermikroklimaat. Die resultate dui in die algemeen daarop dat 'n
eweredige blaarverwydering van 33 % regoor en onderkant die trosse tydens blomvorming of
korrelset tot ertjiekorrelstadium toegepas kan word. Die resultate dui verder daarop dat 33 %van
bestaande geil en lower-verdigte stokke se blare eweredig verwyder kan word op die onderste
helfte van die loot (lower) vanaf ertjiekorrel- of deurslaanstadium. Hierdie hipotese was
suksesvol in die verbetering van lowermikroklimaat, fotosintetiese aktiwiteit en oesmassa.
Vegetatiewe groei is gestrem. Druif- en wynkwaliteit was hoer.
In die geheel kan blaarverwydering soos toegepas in hierdie ondersoek aanbeveel word as
loofbestuurspraktyk ten einde die uitskakeling van nadelige effekte van oormatige vegetatiewe
groei en lowerdigtheid op gebalanseerde metaboliese aktiwiteit, druif- en wynkwantiteit en
kwaliteit, asook langlewendheid en gesondheid van wingerdstokke te bevorder.
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Combinations of Defoliants and/or Desiccants on Cotton Marana Experimental FarmMassey, G. D. 02 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
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Cotton Harvest-Defoliation SchedulingStapleton, H. N., Lepori, Wayne A. 02 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
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Chemical Termination of Cotton FruitingKittock, D. L., Arle, H. Fred 02 1900 (has links)
No description available.
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Cotton DefoliationHazlitt, Jim 02 1900 (has links)
No description available.
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Chemical Termination of Cotton Fruiting in 1975Kittock, D. L., Arle, H. Fred, Bariola, L. A., Henneberry, T. J. 02 1900 (has links)
No description available.
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Conditioning Cotton for DefoliationArle, H. Fred 02 1900 (has links)
No description available.
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