Yields of ZP sweet maize hybrids in dependence on sowing densities

Sweet maize differs from maize of standard grain quality by many important traits that affect the ear appearance, and especially by traits controlling taste. The ear appearance trait encompasses the kernel row number, configuration, row pattern (direction and arrangement), seed set, kernel width and depth, ear shape and size. The quality of immature kernels is controlled by genes by which sweet maize differs from common maize. In order to obtain high-ranking and high-quality yields, it is necessary to provide the most suitable cropping practices for sweet maize hybrids developed at the Maize Research Institute, Zemun Polje. The adequate sowing density is one of more important elements of correct cropping practices. The objective of the present study was to determine the effect of four sowing densities in four ZP sweet maize hybrids of different FAO maturity groups on ear qualitative traits and yields obtained on chernozem type of soil in Zemun Polje. The observed traits of sweet maize (ear length, kernel row number, number of kernels per row, yield and shelling percentage) significantly varied over years. The higher sowing density was the higher yield of sweet maize was, hence the highest ear yield of 9.67 t ha-1 , on the average for all four hybrids, was recorded at the highest sowing density of 70,000 plants ha-1. The highest yield was detected in the hybrid ZP 424su. The highest shelling percentage (67.81%) was found in the hybrid ZP 521su at the sowing density of 60,000 plants ha-1. Generally, it can be stated that sweet maize hybrids of a shorter growing season (FAO 400) could be cultivated up to 70,000 plants ha-1, while those of a longer growing season (FAO 500) could be grown up to 60,000 plants ha-1. In such a way, the most favorable parameters of yields and the highest yields can be obtained

Does Land Use Patterns Matter for Bt-Maize: The Case of Maize Farming System in Kenya

Population pressures and the need to optimize the use of limited available land has led to increasing cropping affluence levels within the maize agro-ecologies in Kenya, and a shift from large to smallholder intensification and multiple cropping patterns. Using a geographic information system, this study relates cropping patterns, by area share, maize productivity and household incomes across maize agro-ecologies, with the purpose to establish a decision support system for optimizing land allocation and in priority setting for introduction of new technologies such as Bt maize varieties. Results show that land use patterns and maize productivity in maize farming systems differ between agroecological zones. The high potential areas experience high maize yields, with maize grown alongside major cash crops such as tea and coffee. In contrast, lowland coastal strip and lake Victoria region tend to grow drought tolerant tuber crops (such as cassava and sweet potatoes) alongside maize in appreciable land sizes. Similarly the dry areas grow drought tolerant legumes such as pigeon pea alongside maize. These low potential areas thus concentrate on meeting their subsistence food self-sufficiency needs, pointing at risk management strategies against drought and pests such as stem borer, unlike high potential areas with high value cash crops. Maize breeders should therefore consider insertion of Bt- genes in maize varieties that would achieve high production and which are also capable of safely growing side by side with crops that meet different food security conditions in different agro-ecological zones in Kenya.Land use, Smallholders, Maize production, Food security, Kenya, Crop Production/Industries, Land Economics/Use,

Substitution of Maize with Cassava and Sweet Potato Meal as the Energy Source in the Rations of Layer Birds

Three hundred and sixty layer hens (36 weeks old Isa Brown) were fed a maize based diet in which sweet potato meal and cassava meal replaced maize in the basal diet during a 12-week trial period. Hen-day egg production was significantly (P< 0.05) depressed lJy cassava meal while birds fed diets with maize and sweet potato meal were not significantly different from each other in hen-day eeg production. Cassava meal significantly reduced (P< O. 05) metabolizable energy intake while there was no significant difference in the crude protein intake of birds fed sweet potato and cassava meal. There was, however, no significant effect from replacing maize with sweet potato or cassava meal on egg, weight, feed intake, shell thickness, Haugh unit, feed/dozen eggs or feed/kg egg (p<0.05). The maize control diet was superior (P< O. 05) in the digestibility of crude protein while energy digestibility was depressed (P< 0.05) with the cassava diet

Breeding of maize types with specific traits at the Maize Research Institute, Zemun Polje

Maize is primarily grown as an energy crop, but the use of different specific versions, such as high-oil maize, high-lysine maize, waxy maize, white-seeded maize, popping maize and sweet maize, is quite extensive. Speciality maize, due to its traits and genetic control of these traits, requires a particular attention in handling breeding material during the processes of breeding. It is especially related to prevention of uncontrolled pollination. In order to provide successful selection for a certain trait, the following specific procedures in evaluation of the trait are necessary: the estimation of a popping volume and flake quality in popping maize; the determination of sugars and harvest maturity in sweet maize; the determination of oil in selected samples of high-oil maize types, and so forth. Breeding programmes for speciality maize, except high-amylose maize, have been implemented at the Maize Research Institute, Zemun Polje, Belgrade, for the last 45 years. A great number of high-yielding sweet maize hybrids, popping maize, high-oil and high-lysine, flint and white-seeded maize hybrids were developed during this 45-year period. Auspicious selection and breeding for these traits is facilitated by the abundant genetic variability and technical and technological possibilities necessary for successful selection

D 5.5.1.1. Final report on sensory testing in Africa for Group 1. Project AFTER “African Food Tradition rEvisited by Research”

This deliverable concerns the sensory evaluation of the reengineered group 1 African products in the AFTER project. Specifically, it related to reengineered akpan and gowe from Benin, kenkey from Ghana and Kishk Sa'eedi in Egypt. Concerning reengineered akpan from Benin, the sensory evaluation was undertaken in Montpellier, France. Re-engineering of akpan has focused primarily on improvement of sanitary properties of the product, which was a great achievement and will allow producing Akpan on a larger scale in SMEs in Africa. Sensory evaluation of the Akpan products was carried out using CATA and JAR techniques that have been developed for use with consumers instead of a trained panel. Three Akpan products were tested by 102 consumers: Akpan added with 10% sugar (AS10), Akpan added with 3% spray-dried milk and 8.7% sugar (AMS8.7) and Akpan added with 3% spray-dried milk and 15% sugar (AMS15). Independently of the Akpan tasted, Acidity or Sweetness attributes were scored “Just About Right, as I like” by 56 to 77% of consumers. Odour perception was perceived differently, depending on consumers. However, Texture was found “Too weak”, too liquid by the majority of consumers (49 to 55%) and Taste “too strong” (46 to 54%). The most frequently CATA descriptors checked by consumers which better described Akpan products were: “Artificial”, “Floral”, “New/Different”, “Strong in Taste”, “Mealy”, followed by “Liquid”, “Drinking yoghurt”, “Sweet”, “Acidic”, and “Rough”. At the opposite, an ideal-yoghurt was described as Creamy, Natural, Good for health, Refreshing, Homogeneous, with a texture of a Bulgarian yoghurt-type, Thick, Sweet, Attractive, Nutritious and Milk taste. In terms of sensory evaluation, the three Akpan products did not significantly. If we remove the terms such as “artificial”, “strong in taste”, “floral” due to a manufacturing error (use of a few drops of citronella essential oil instead of citronella infusion as a traditional flavouring of Akpan in Benin), it remains the terms “mealy”, “liquid” “drinking yoghurt” that better describe the product and were previously used for describing traditional Akpan product. This suggests that sensory properties of the reengineered Akpan may not be acceptable to French consumers who prefer a product with a creamy, homogeneous, Bulgarian yoghurt-type taste. Gowe in Benin was not tested using sensory evaluation. Sensory testing of Gowe in Benin was not undertaken because this was planned to be undertaken in Europe. The reason is because the methodology used in sensory evaluation is independent of the location provided the samples are the same. However, the particular samples provided for French sensory testing contained a concentration of aflatoxin that was higher than the minimum EU allowable limit. It was not possible to repeat the sensory test in France because it would have taken too long to obtain a replacement supply from Benin and to repeat the processing (takes one week). In which case the samples would have been took different to enable a comparison. The sensory evaluation of kenkey was carried at the Food Research Institute, Ghana. Current trends in urbanization, and the increasing popularity of kenkey among consumers, require larger scale production with consistent quality. Testing was conducted to determine the sensory profile of white reengineered kenkey made using the optimum pre-process conditions of steeping time (30 and 45h), steeping temperature (30ᵒC and 35ᵒC) and dough fermentation time of 12 hours. The qualitative descriptive analysis showed that the sensory profile of white kenkey was dependent on preprocessing variables. Thus merely optimizing the pre-processing variables with regards to acid production and other readily measurable constituents though could shorten the production process could not guarantee the best product sensory quality. The results show that all the descriptors generated were appropriate for differentiating sensory qualities among samples and could be used for basic research and product development for white kenkey. Soft and sticky texture in white kenkey was highly appreciated. Sensory evaluation of Kishk Sa'eedi (KS) was undertaken in Egypt. KS is an Egyptian indigenous wheat-based fermented food prepared traditionally according to the method applied by Upper Egyptians. This work is done to characterize sensory properties and sensory profile of the reengineered KS. Quantitative descriptive analysis (QDA) coupled with principal component analysis (PCA) was used to study the interrelationship among and between sensory attributes. 14 terms regarding appearance, odour, flavour and texture of the samples, was selected and a glossary describing each descriptor was developed. Three KS samples were profiled by 11 assessors using the chosen 14 sensory descriptors. Mean intensity ratings of the descriptive attributes showed that there were significant differences (p<0.05) within KS samples for all the 14 attributes tested. In general, high ratings for creamy colour, fresh odour, KS taste and fracturability are considered as positive effects that would be favoured by panellists while increase in caramel colour, sour taste, denseness and mouth coating are regarded as undesirable. The re-engineered KS sample perceived as less sour and less salty compared with the traditional ones. With regard to texture quality, reengineered sample was easy to fracture, and scored higher for grittiness. Meanwhile, the sample was rated lower than the traditional ones with regard to Kishk taste and fermented odour. Descriptive sensory evaluations between of the traditional and re-engineered KS samples showed that tastes i.e. sour, salty, and KS taste; fracutability and grittiness were discriminating attributes. Fermented odour, colour i.e. creamy and caramel; presence of fissure and presence of bran were least discriminating. Evaluation of the KS sensory characteristics provide in depth understanding of the sensory quality criteria as perceived by the sensory trained panel. The present study showed that substantial differences in sensory character were noted between the traditional and re-engineered KS in particular, differences in colour, fresh odour, KS taste, fracutability and mouth coating. This work showed that the application of QFD and PCA techniques could provide the useful information to KS and helped to identify the importance of product attributes. In conclusion the sensory evaluation showed clear sensory differences between the traditional and reengineered products relating to akpan from Benin, kenkey from Ghana and Kishk Sa'eedi from Egypt. Other deliverables will report on the acceptance by consumers

Taro leaf and stylo forage as protein sources for pigs in Laos

Existing forage plants may have applications as alternative protein resources for pigs in smallholder farming systems. This thesis examined the effect of harvesting/defoliation interval on the yield and chemical composition of taro leaves and stylo forage and analysed appropriate ensiling methods for these materials. The effect of replacing soybean crude protein (CP) with ensiled taro leaf and stylo forage CP on growth performance and carcass traits of LY (Landrace x Yorkshire) and ML (Moo Lath) pigs was also examined. Taro leaf and petiole dry matter (DM) yield increased with increased harvesting frequency in the two years studied, but there was no effect on tuber yield. The leaves contained 160-260 g CP kg¹ DM. Stylo leaf DM yield was unaffected by harvesting interval in the first year, while leaf DM yield was larger with the most frequent harvesting in the second year. The leaves contained 170-235 g CP kg¹ DM, which was much higher than in the stems or forage (leaves+stems). Use of cassava root meal, sugar cane molasses and taro tuber meal as silage additives affected pH and the DM, ash and NDF content of stylo forage and taro leaf silage, and the NH₃-N content of stylo forage silage. Level of additive affected pH and DM, NH₃-N, CP, ash and NDF content in taro silage, but not NH₃-N, CP and NDF content in stylo forage silage. Increasing duration of ensiling reduced pH and DM content in stylo forage and taro leaf silage. Dry matter intake (DMI) and CP intake (CPI) in growing LY and ML pigs were unaffected by increasing replacement (25 and 50%) of soybean CP by taro leaf silage CP in the diet, whilst for stylo forage silage DMI and CPI were highest when 25% of soybean CP was replaced. Average daily weight gain and feed conversion ratio (FCR), carcass weight, back fat thickness and dressing percentage were unaffected by increasing replacement of soybean CP with taro leaf or stylo forage CP in the diet. LY pigs had higher intake and better carcass traits than ML pigs. The work confirmed that stylo forage and taro leaves can be used as protein sources in smallholder pig production systems without negative effects on the performance of growing LY and ML pigs

The effect of breed and feed-type on the sensory profile of breast meat in male broilers reared in an organic free-range system

1. Studies on the sensory profiling of male broiler breast meat were carried out to evaluate the effect of two very different broiler breeds (JA757 and New Hampshire), two different feed types (broiler and grower feed) and age at slaughter (82 and 110 d). 2. The sensory profiling consisted of a pilot study, 4 training sessions, and finally the assessment. During the training session a panel of 9 assessors defined 17 attributes, which were used to describe the smell, texture and flavour of the breast fillets. Each attribute was evaluated on a 15-cm unstructured line scale. 3. The breast meat became significantly less hard, and more juicy and tender in the New Hampshire at 110 d of age, whereas the opposite was found in JA757, which also acquired a more ‘‘sourish’’ flavour with age. The smell of ‘‘sweet/maize’’ and ‘‘bouillon’’ became weaker with age in JA757, but not in New Hampshire. 4. Several significant differences in relation to the main factors of breed and age were found. The traditional broiler hybrid JA757 did best for most smell and flavour attributes, whereas New Hampshire did best for the texture attributes. Age had a negative effect on the flavours and smell attributes ‘‘fresh chicken’’, ‘‘neck of pork’’ and ‘‘sweet maize’’, but a positive effect on the texture attribute ‘‘crumbly’’. In addition meat was more ‘‘stringy’’ at 110 d of age. 5. The flavours ‘‘neck of pork’’ and ‘‘umami’’ were significantly improved when JA757 was fed on the broiler feed and when New Hampshire was given the grower feed. The meat smelt more ‘‘sourish’’ at 82 d of age and less ‘‘sourish’’ at 110 d of age when the grower feed was consumed. Meat was significantly harder and stringier when JA757 was fed on the grower feed. This was not the case for New Hampshire. In general, the meat was significantly less crumbly and stringier with the grower feed. 6. Overall a very distinct difference in sensory profile was found between the two breeds. In addition different slaughter ages and feeding strategies should be taken into consideration in a niche production based on alternative genotypes

Environmental Policy Update 2012: Development Strategies and Environmental Policy in East Africa

The seven chapters that comprise this report explore ways to integrate sustainability goals and objectives into Ethiopia's current development strategies