School of Agriculture, Food and Ecosystem Sciences - Theses
Permanent URI for this collection
Search Results
1 - 10 of 15
-
ItemRoasted legumes for lambs( 1997)Whole lupin (Lupinus angustifolius) and narbon bean (Vicia narbonensis) seeds were dry roasted at 100, 110, 120, 130, 140, 150 and 160C for 15, 30 and 45 minutes. The effect of roasting on in vitro solubility of crude protein (CP) and 'dry matter digestibility (IVDMD) were determined. From the solubility results, seeds roasted at 130C for 15, 30 and 45 minutes were chosen to study the effect of roasting on in situ ruminal disappearance of CP and dry matter (DM). From the in situ results seeds roasted at 130C for 45 minutes were chosen to be fed to crossbred wethers for nine weeks in a 2 (grain legumes) x 2 (raw vs roasted) experiment, in rations consisting of 70% concentrate (legume seed + barley) and 30% roughage (lucerne + oaten chaff). The effect of roasting on feed intake, growth, dry matter and nitrogen digestibility, nitrogen utilization, carcass weight and fat thickness were determined. For both legumes, CP solubility decreased with increasing temperature and time of roasting. The decrease was slightly lower in narbon than in lupin. CP solubility of lupin was decreased from 84.7% (raw) to 17.3% (160C, 45 min) and that of narbon from 68.0% (raw) to 18.3% (160C, 45 min). Dry roasting had no significant (P<0.05) effect on IVDMD measured over 72 hours. In situ DM and CP disappearance was estimated by incubating nylon bags in the rumen of sheep for 2, 6, 12 and 24 hours. Dry roasting significantly (R<0.05) reduced disappearance of CP from the bags with the reduction being slightly greater for lupin (a difference of 17.8% between the raw and 45 min sample after 24 hours of incubation) than narbon (a difference of 15.0% between the raw and 45 min sample after 24 hours of incubation) but had no significant effect on DM disappearance after 24 hours of incubation. Feed intake, growth, feed conversion ratio, dry matter digestibility, carcass weight and fat thickness were not affected (P>0.05) by roasting. Nitrogen retention, expressed as a percentage of nitrogen intake or as a percentage of nitrogen absorbed, was significantly (R<0.05) higher for lambs fed diets containing roasted narbon than for lambs fed diets containing raw narbon (as % of intake 20.3 is 12.3; as % of absorbed 25.6 vs 15.4), but was lower for lambs fed diets containing roasted lupin than those fed diets containing raw lupin (as % of intake 23.1 vs 30.9; as % of absorbed 27.3 vs 37.4). Dry roasting of lupin and narbon bean seeds decreased in vitro CP solubility and reduced ruminai disappearance of CP. Nitrogen utilization in lambs fed diets containing roasted narbon seeds was improved. Roasted lupin significantly (R<0.05) reduced nitrogen utilization in lambs. However, roasting these legumes had no significant (R>0.05) effect on growth.
-
Item
-
Item
-
ItemPhysiological and morphological responses of several genotypes of tropical and sub-tropical maize (Zea mays L.) to water and nitrogen deficit during the early vegetative phase( 1997)Intermittent drought combined with nitrogen stress during early growth of maize crops in the tropics limits maize production in developing countries. Plant morphological and physiological responses of different maize genotypes to two aspects of stress, water deficit and nitrogen stress, were examined during the growth of several maize genotypes. Eight maize genotypes including three inbred lines (Gn 160, Gn 106, Gn 175), three single crosses (Gn 160 x Gn 175, Gn 106 x Gn 175, Gn 106 x Gn 160) and two open pollinated cultivars (Tuxpeno Sequla Cycle 0, drought sensitive; Cycle 8, drought resistant) were examined for drought tolerance during early growth. Variables used for assessing tolerance were dry weight of shoot and root, leaf area, relative water content, water potential and stomatal conductance which were measured in both well-watered and the respective droughted treatments for each genotype. Under growth room conditions, the level of severe drought imposed caused a substantial reduction in growth of eight maize genotypes, relative to the respective well-watered conditions. The single cross Gn106 x Gn160 revealed drought tolerance traits in shoot and total biomass, which were higher than the other single crosses. It is concluded that this single cross is more drought-tolerant than the other single crosses during early growth stages. Tuxpeno Sequla Cycle 0 and Cycle 8 had similar shoot and total biomass under both water regimes, and did not show differences in drought tolerance during early growth. There was no clear indication of transmissability of drought tolerance from parent lines to their respective single crosses. The combined effects of drought and timing of N stress during early growth on morphological and physiological traits, which were altered during later growth and yield components, were investigated in two related tropical maize cultivars, Tuxpeno Sequla Cycle 0 (Tux. CO) and Cycle 8 (Tux. C8), which were selected for drought sensitivity (Tux. CO) and tolerance (Tux. C8), during flowering under glasshouse conditions. Total biomass at maturity and green leaf number below the ear at grain filling were similar between Tux. CO and C. 8 under different water regimes. Increased grain yield and harvest index in Tux. C8, compared with Tux. CO, resulted mainly from increased kernel number per row and rows per ear. Tux. C8 was not only higher in yield but also higher in N use efficiency than Tux. CO when experiencing moisture and N stress during early growth. Shoot biomass under moderate drought versus well-watered conditions was found to be more sensitive than root biomass in both Tux. CO and C8. Under drought compared with well-watered conditions, stem biomass was more sensitive than leaf biomass. Leaf area in the high-N treatments was more sensitive to water deficit than in low N treatments, as indicated by the fact that droughted plants in the early N application (NE) and split (NS) treatment produced lower leaf areas than well-watered plants, while in the control (NO) and late N (NL) treatments there was no significant difference in leaf area between drought and well-watered conditions. Early N application resulted in a shorter time from sowing to anthesis than later N application. Clearly N stress is the main limiting factor for growth and yield of maize under moderate level of water deficit. This study revealed that maize plants require N for growth and dry matter accumulation as early as immediately after seedling emergence even under low N input conditions (75 kg N per hectare). Increased grain N content and nitrogen harvest index for a split N application resulted from increased N content in the stem and leaf Even under low N input conditions i.e. the application equivalent to 75 kg N/ha in this experiment, N still needed to be supplied as a split application, in order to increase N use efficiency. Nitrogen harvest index under well-watered conditions was higher than that under drought, indicating that water deficit also had an effect on nitrogen harvest index of both cultivars (CO and C8) under different level of N treatments.
-
ItemThe use of informal credit by smallholder farmers in Fiji( 1997)Smallholder farmers often use informal credit because formal financial systems are unable to provide the types of financial services that they need. Besides strengthening the production base, informal credit provide linkages among credit, tenure and marketing arrangements. Informal credit is already a component of the interpersonnel relation network of the farming community and of considerable importance for income generating activities and consumption. The literature reviews economic studies and surveys in less developed countries notably South Asia and Africa. It substantiates the importance of informal credit amongst smallholder farmers. It persists in the rural sector because it provides valuable services to the rural people. In Fiji, increasing interest in the private sector, concern about the lack of financial service to the agriculture sector and disappointment over results from official government programmes have led planners to search for alternative strategies. The informal credit system which has been underestimated due to prejudices and a lack of awareness that is well adapted to the complex conditions in rural areas. A better understanding of the informal system requires a study, including the implications for establishing an appropriate institutional infrastructure for supplying credit to the smallholder farmers. The case study research developed in this project describes different patterns of use of informal credit between village and settlement farmers. Commercialisation of agriculture and the land tenure system have contributed to a dualistic structure of both agriculture and informal credit systems. On one hand, semi-subsistence agriculture is common within the traditional 'sharing' system based on kinship: on the other, the more commercially-oriented agricultural systems operate within the open financial markets. The basic features include an extensive non-legalized sharefarming system, sharing of draught animals, inputs, farming implements, labor, joint marketing contracts; and small loan transactions, many for consumption needs. There is no enforcement mechanism but for an understanding that repayment will be made someday, directly or indirectly. Informal credit is found to be frequently used to compensate for low income or low returns to investment. Furthermore, it provides for sudden consumption needs and is usually promptly available. The informal credit comprises a wide array of credit arrangements based, in part, personal relationships and traditions outside the legal framework. An assessment of the volume, value and costs of transactions is proposed to be the next research challenge.
-
Item
-
Item
-
Item
-
ItemAssessment of the adoption of soybean production technology in the province of Isabela, Philippines( 1997)The study assessed the extent of adoption of a soybean package of technology (POT) and explored factors which influence adoption and non-adoption of the technology by smallholder farmers in the Province of Isabela, Philippines, an area not customarily planting soybeans. The study also explored the question whether the institutional environment supported adoption and was favourable to the needs and resources of the farmers. A structured questionnaire was, used in the survey to gather the information from the 80 farmer-respondents, randomly selected in four villages in Isabela Province. Information collected was: farmer characteristics and resources; farming system; sources of information about farming; information on soybean farmers, technology and institutional-related factors; farmers' opinions about the POT (i.e. profitability, problems, recommendations and sustainability). This information helped understand the factors that influence adoption patterns. The study showed that a high proportion of respondents were familiar with the POT. All 80 respondents knew of soybean; 73 were familiar with the POT and had planted soybeans. However, only 32 of respondents had continued to a second or further planting. Results showed that there are several factors which influence farmers' decision towards technology adoption including characteristics of technology, farmer characteristics and resources, farming system and institutional factors. Most farmers modified the recommended practices based on their financial capability, local situations and past experience. It was observed that positive attributes of a technology may not be sufficient to ensure adoption. Institutionally-related support such as credit assistance, marketing assistance and guaranteed price, extension services, source of inputs, infrastructure and supporting policy must be present to motivate farmers to adopt and maintain an, innovation or technology. Also, in this study it was observed the importance of personal or face to face communication with the farmers to encourage adoption. The study yielded some recommendations which could be instrumental in setting future directions to enhance the soybean industry in the country.
-
ItemThe role of ponies in the agricultural systems of Sumbawa Island, West Nusa Tenggara Province, Indonesia( 1997)This study defines the role of ponies in the current agricultural systems of Sumbawa island, NTB Province, Indonesia. A questionnaire and a recording form were used for data collection. One hundred pony farmers were interviewed and 81 adult ponies were assessed in kampung (village) Ngeru, Sumbawa district. The results shows that ponies are mainly used for ninting (trampling grain, ie, soybean and mungbean) and as pack animals to carry agricultural products from farm to home. Some are used for riding and racing. Apart from these, the main priority of raising ponies is to provide an additional source of income and saving. Even though the number of ponies slaughtered in Lombok island has increased, consumption of pony meat in Sumbawa island is not common. The feeding system is mostly grazing-based, with cut-and-carry for racing ponies. August to October is the period when there is limited grass in the grazing area (eg, forest, rainfed land). Because most farmers use grazing-based systems, breeding and health management is not practised due to the difficulty in controlling ponies at distant locations. Results also indicate that there is a strong preference for rearing ponies compared with cattle but buffalo are the most preferred large animal in the area of study. Farmers keep ponies because of their contribution to the farming operation and their ability to find feeds in distant areas. However, the population of ponies is predicted to decrease as a result of economic development and population pressure in the island. The constraints affecting the population will be the competition for grazing with other animals (eg, buffalo and cattle) and limited uses in the future. Research may slow the forecast reduction in numbers.