Syncarpha recurvata (L.f.) B. Nord. (Asteraceae, Gnaphalieae) is listed as a vulnerable (intermediate priority) species. The propagation methods of achene germination, stem cuttings, air layering and micropropagation were investigated to obtain an efficient propagation method. Smoke water dilutions of 1:100, 1:50 and 1:10 significantly increased germination, with the 1:100 smoke water dilutions showing the highest germination percentage (22.4 percent). Achenes collected between August and October 2005 showed higher germination and viability than achenes collected between May and July 2006. Fifty percent of the stem cuttings and 32 percent of the airlayered branches rooted. Embryo culture was the only successful culture type out of the four attempted. Two embryos germinated and four became photosynthetic. Two of the germinated embryos also produced callus cells, a medium supplemented with 5 μM IAA may be used to test for a suitable plant regulator for organogenesis or embryogenesis. Syncarpha recurvata plants were also transplanted into pots and 60 percent survived. A growth rate of 1.466 mm y-1 was obtained from total shoot length measurements. In this study, it was found that air-layering branches of transplanted Syncarpha recurvata plants is the most efficient propagation method.

Thesis (MScAgric)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: Poor water management and poor water use efficiency (WUE) have been identified as one of the major problems experienced by vegetable growers in most of the developing countries, including South Africa. This poor management and poor utilization of water have led to a drastic decline in the quality and quantity of available water. In South Africa agriculture uses about 50% of available water. Increasing water demand for domestic, industrial and mining uses, may decrease agriculture's share to less than the current 50%, henceforth, better utilization of this resource is imperative. Selection of a good irrigation system can limit water loss considerably. Some irrigation systems have a potential to save more water than others do. Since irrigation systems affect the WUE of crops, care should be taken when selecting an irrigation system under conditions of limited water quantity. Ebb-and- Flood watering systems have been introduced for effective sub-irrigation and nutrient delivery within closed systems. Such a system was adapted in South Africa, to develop a vegetable production unit for use by families in rural communities, while saving substantial amounts of water. A need to further improve the WUE of this system was subsequently identified. Two studies were conducted at the experimental farm of the University of Stellenbosch (Department of Agronomy). The first trial was conducted under controlled conditions in a glasshouse, and the second under open field conditions. In the first trial, Beta vulgaris (Swiss chard) and Amaranthus spp. ('Imbuya') were grown in two root media; gravel and pumice. In addition, an 'Ebb-and-Flood' and a 'Constant level' system were used with nutrient solutions at two electrical (EC) conductivity levels 1.80 and 3.60 mS cm-I. The results of this (2x2x2x2) factorial experiment indicated that a combination of the 'Ebb-and-Flood' system with gravel as a root medium produced the best results at a low EC, when 'imbuya' was used. A high total WUE was found with 'imbuya', (7.35 g L-I) at EC 1.80 mS cmicompared to a relatively low WUE of 5. 90 g L-I when the 3.60 mS cm-I nutrient solution was used. In the second trial, 'Imbuya's' foliage dry mass, leaf area and WUE was evaluated under field conditions at the Stellenbosch University experimental farm, during the summer of2002. The experimental farm (33°55'S, 18°52'E) is situated in the cooler coastal wine grape-producing region of South Africa with a relatively high annual winter rainfall. This trial was conducted on an alluvial soil, with clay content of 25% and a pH of 5.9 (KC!). A closed 'Ebb-and-Flood' system was compared with two open field irrigation systems ('Drip' and 'Flood') using nutrient solutions at two electrical conductivity levels (1.80 and 3.60 mS cm-i) in all three cases. Foliage dry mass, leaf area as well as WUE was best with 'Drip' irrigation, when a nutrient solution with an electrical conductivity of 3.60 mS cm-i was used. In spite of the fact that additional ground water was available for the soil grown 'Drip' and 'Flood' treatments, the 'Ebb-and-Flood' system outperformed the 'Flood' treatment, especially when the nutrient solution with an EC of 3.6 mS cm-i was used. Insufficient root aeration in the flooded soil could have been a contributing factor. The fact that the 'Ebb-and-Flood' and 'Drip' systems gave the best results when the high EC solution was used to fertigate the plants, may indicate that the plants could have hardened due to the mild EC stress, better preparing them to adapt to the extreme heat that was experienced in the field. / AFRIKAANSE OPSOMMING: Swak: bestuur van water en 'n swak: water-gebruik-doeltreffendheid (WOD) is as een van die belangrikste probleme geïdentifiseer wat deur groente produsente in die meeste ontwikkelende lande, insluitend Suid-Afrika, ervaar word. Hierdie swak bestuur en benutting van water het daartoe bygedra dat 'n drastiese afname in die kwaliteit asook in die kwantiteit van beskikbare water ervaar word. In Suid-Afrika gebruik die landbou-sektor ongeveer 50% van die beskikbare water. Toenemende water behoeftes vir huisgebruik, industrieë en die mynbou mag hierdie 50% aandeel van die landbou sektor laat krimp. Beter benutting van hierdie skaars hulpbron is dus noodsaaklik. Die keuse van goeie besproeiingsisteme mag waterverliese merkbaar beperk aangesien sekere sisteme se water-besparingspotensiaal beter as ander is. Aangesien besproeiingstelsels die WOD van gewasse beïnvloed, is spesiale sorg nodig waar 'n besproeiingstelsel onder hierdie toestande van beperkte waterbronne gekies moet word. 'Ebb-en-Vloed' sisteme kan aangewend word om water en voedingselemente van onder in 'n wortelmedium te laat opstoot en in 'n geslote sisteem te laat terugdreineer. So 'n sisteem is in Suid-Afrika ontwikkel waarmee groente vir families in landelike gebiede geproduseer kan word terwyl water bespaar word. 'n Behoefte om die WOD van hierdie produksiesisteem verder te verbeter is egter geïdentifiseer. Twee ondersoeke is by die Universiteit van Stellenbosch se proefplaas (Departement Agronomie) gedoen. Die eerste proef is onder beheerde omgewingstoestande in 'n glashuis uitgevoer en die tweede onder veld toestande. In die eerste proef is Beta vulgaris (Snybeet) en Amaranthus spp. ('Imbuya') in twee tipes wortelmedia; gruis en puimsteen verbou. 'n 'Ebb-en-Vloed' asoook 'n 'Konstante vlak' besproeiingsisteem is gebruik terwyl voedingsoplossings ook by twee peile van elektriese geleiding (EC) teen 1.80 en 3.60 mS cm-I toegedien is. Die resultate van hierdie (2x2x2x2) fakroriaal eksperiment het aangetoon dat 'n kombinasie van die 'Ebb-en-Vloed' sisteem met gruis as 'n wortelmedium die beste resultate teen 'n lae EC lewer waar 'imbuya' gebruik is. Die WOD met 'imbuya' was hoog (7.35 g L-1) by 'n EC van 1.80 mS cm-I, vergeleke met 'n relatief lae WOD van 5. 90 g L-1 waar die 3.60 mS cm-I voedingsoplossing gebruik is. In die tweede proef is 'Imbuya' se droë blaarmassa, blaar oppervlakte en WOD onder veldtoestande op die Universiteit van Stellenbsoch se proefplaas in die somer van 2002 ge-evalueer. Die proefplaas (33°55'S, 18°52'E) is in die koeler kusstreke van die wyndruif produksiegebied in die winterreëngebied van Suid-Afrika geleë. Hierdie proef is op alluviale grond met 25% klei en 'n pH van 5.9 (KCi) uitgevoer. 'n Geslote 'Ebb-en-Vloed' sisteem is met twee veld-besproeiingsisteme vergelyk ('Drup' en 'Vloed') terwyl voedingsoplossings teen twee peile van elektriese geleiding (1.80 en 3.60 mS cm-I) in al drie gevalle gebruik is. Blaar droëmassa, blaaroppervlakte asook die WGD was die beste met 'Drup' besproeiing waar die EC van die voedingsoplossing 3.60 mS cm-I was. Ten spyte van die feit dat ekstra grondwater vir die 'Drup' and 'Vloed' behandelings beskikbaar was, het die 'Ebben- Vloed' stelsel beter as die 'Vloed' behandeling gedoen veral waar die voedingsoplossing se EC 3.6 mS cm-I was. Swak wortelbelugting was waarskynlik die rede waarom vloedbesproeiing swak produksie gelewer het. Die feit dat die 'Drup' en die 'Ebb-en-Vloed' behandelings in die veldproef die beste gedoen het waar die EC hoog was, mag moontlik met die gehardheid van die plante verband hou wat aan ekstreem warm en dor toestande blootgestel was.

Submitted by Liliane Ferreira (ljuvencia30@gmail.com) on 2018-04-20T15:44:20Z No. of bitstreams: 2 Dissertação - Frederico Rodovalho de Oliveira - 2018.pdf: 2263442 bytes, checksum: cbb8bc9baf7eeb48e475bd0b59f97f64 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-04-23T11:53:43Z (GMT) No. of bitstreams: 2 Dissertação - Frederico Rodovalho de Oliveira - 2018.pdf: 2263442 bytes, checksum: cbb8bc9baf7eeb48e475bd0b59f97f64 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-04-23T11:53:43Z (GMT). No. of bitstreams: 2 Dissertação - Frederico Rodovalho de Oliveira - 2018.pdf: 2263442 bytes, checksum: cbb8bc9baf7eeb48e475bd0b59f97f64 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-03-26 / The onion is a vegetable consumed by a large part of the world population. Brazil occupies an important position on the world stage, ranking ninth among the largest producers. Most of the national production is concentrated in the Southern Region, which accounts for 45% of the onion production in the country. The state of Goiás currently ranks sixth among the largest domestic producers, accounting for 14% of Brazilian production. The literature on the marketing of horticultural products indicates the existence of a concentration process, which is exercised by the wholesale market, but it is also worth mentioning the fact that the retail market influences the productive chain due to the market power of the large supermarket chains. Thus, the objective of this work is to analyze the existence of Asymmetry in Price Transmission (ATP) among the agents of the onion production chain in Goiás. For the conduction of the study it was necessary to use econometric models such as the one developed by Houck 1977). In general terms, the results indicate that 30% of the income from the sale of the onion, are directed to the rural producer, and the rest is divided between the wholesale market and the retailer. In addition, the results show that asymmetry occurs in the speed of transmission of prices among the agents of the onion production chain, with relative advantage to retail over the other productive links. / A cebola é uma hortaliça consumida por grande parcela da população mundial. O Brasil ocupa importante posição no cenário mundial, ficando com a nona posição entre os maiores produtores. A maior parte da produção nacional está concentrada na Região Sul, que é responsável por 45% da produção de cebola no país. O estado de Goiás atualmente ocupa a sexta posição entre os maiores produtores nacionais, respondendo por 14% da produção brasileira. A literatura sobre comercialização de produtos hortifrutigranjeiros indica a existência de um processo de concentração, que é exercido pelo mercado atacadista, mas merece destaque também, o fato de o mercado varejista influenciar a cadeia produtiva, devido ao poder de mercado das grandes redes de supermercados. Dessa forma, o objetivo deste trabalho é analisar a existência de Assimetria na Transmissão de Preços (ATP) entre os agentes da cadeia produtiva da cebola em Goiás. Para a condução do estudo foi necessário o uso de modelos econométricos, como o desenvolvido por Houck (1977). Em termos gerais, os resultados apontam que 30% da renda pela venda da cebola, são direcionados para o produtor rural, e o restante é divido entre o mercado atacadista e o varejista. Além disso, os resultados mostram que ocorre assimetria na velocidade de transmissão de preços entre os agentes da cadeia produtiva da cebola, com vantagem relativa para o varejo sobre os demais elos produtivos.

Thesis (M.Sc. (Agriculture)) --University of Limpopo (Turfloop Campus), 2008 / A large number of emerging farmers in South Africa is involved in subsistence agriculture as a result of poor resource endowment or due to other constraints. Relatively few agricultural products from emerging farmers reach the formal agricultural market. Livestock production is common among emerging farmers and a large proportion of the national livestock is in the hands of the rural poor. Horticultural crops are generally perishable and require immediate disposal, thus implying that the farmers who produce horticultural crops do so with intention to sell their products. Most studies tend to group farmers regardless of their line of production. Only few studies have attempted to investigate the socioeconomic characteristics of farmers, differentiating the commodities that they produce. The objective of this study is to identify and compare the socioeconomic characteristics that determine the farm income of the emerging livestock farmers and horticultural farmers in South Africa. Such an analysis would allow more targeted policy responses for different groups of emerging farmers. The data used in this study consisted of 202 livestock farmers and 126 horticultural farmers selected through quota sample covering all nine provinces in South Africa. The data were collected by the Development Bank of Southern Africa in 2005. Descriptive Analysis and Discriminant Analysis are applied to determine the factors that matter the most in determining incomes of livestock and horticultural farmers. Farm iv income is used as the dependent variable, and fourteen independent variables were identified. The factors that matter the most in determining livestock farmers’ income are, namely access to finance, farm size, age of the household head, membership to farmer organizations and government support. The factors that matter most in determining horticultural farmer’s income are namely farm size, age of the household head, land type (land ownership), and extension services. The results of this study showed that access to land and age of the household head matter the most to both livestock and horticultural farmers. The study found that poor access to land is one of the major constraints facing emerging farmers in South Africa. Land is also one of the factors that may determine the amount of credit the emerging farmers can obtain and, if farmers produce on communal land, it becomes harder to obtain credit. Memberships to farmer’s organisations, government support and access to finance are characteristics that matter the most to livestock and do not seem to matter that much to horticultural farmers. Farmer organisations often lobby for collective provision of appropriate and needed services for their membership. The services that are often lobbied for are services such as extension, marketing and provision of training to empower women and young people so as to enable them to participate fully in farming activities. The results of this study show that there are differences in socio-economic characteristics that matter the most in determining farm income for livestock and horticulture farmers. v Horticulture farmers should be given much support to improve access to get enough land and training while in livestock farming assistance focus should be on access to finance and support services. vi

This investigation was planned to study the new dormant spray, dinitro-ortho-cyclo-hexyl-phenol in relation to its use under Virginia conditions for the control of certain insects with which the Virginia orchardist has constantly to deal. The object of this study is to determine what affects the varying amounts of dinitro-ortho-cyclo-hexyl-phenol, either in oil or water sprays with different emulsifiers, has on penetration, injury and effectiveness. Conclusions which may be drawn from the work discussed in this thesis are: (1) That the 50 per cent goulac and 50 per cent bentonite emulsifier used at the rate of 1.25 pounds per 100 gallons is seemingly the best material among those tested. However, under the conditions in which trials were made this year, a dry form of dinitro-ortho-cyclo-hexyl-phenol mixed with an emulsifier containing bentonite and soy flour appears to be superior in preliminary tests, either in oil or water sprays, due to its better wedding power. (2) That injury which has been examined apparently occurs at the bud and enters the branch through the bud. (3) That the dinitro-ortho-cyclo-hexyl-phenol in oil and water sprays should be applied only in the dormant season, although no serious injury has followed its use in the plots used for this study even when the buds have pushed out leaves as much as one quarter of an inch. (4) That in the plots treated, the powder and water form of dinitro-ortho-cyclo-hexyl-phenol gave satisfactory control of Rosy aphis. (5) That time, care and the following of directions should not be sacrificed in the making up of the emulsions. / Master of Science