Fermentation kinetics of stems of sorghum and millet genotypes

Gas production profiles were obtained from in vitro fermentation of stems of six genotypes of sorghum and millet grown at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), India. The ranking of sorghum and millet genotypes by cumulative gas production was consistent throughout the 96-hour fermentation period. However, differences were proportionally greater during the initial 3 and 6 h of fermentation. The multiphase model described by Groot et al. [Groot, J.C.J., Cone, J.W., Williams, B.A., Debersaques, F.M.A., Lantinga, E.A., 1996. Anim. Feed Sci. Technol. 64:77–89] was used to fit the in vitro fermentation gas observations of these substrates, and fermentation kinetics parameters were calculated using the fitted model. The final estimates of the model parameters (A, B, C), tested by varying the initial estimates obtained with the monophasic model by ±50%, were stable, showing no dependence on the starting values of the model parameters. However, in millet stems, the C parameter has shown a tendency to converge near unity. The stability of the final values of the parameters of the model in this study suggests the potential applicability of the multiphase model when only nine gas observations over a period of 96 h were available. However, the indeterminacy in the parameters of phase 1 for some millet stems indicates the need of an intermediate gas value between 0 and 3 h. In both, sorghum and millet the asymptotic gas of the first phase (A1) was negatively correlated with NDF (r = −0.82, p < 0.05; r = −0.80, p < 0.05, respectively) and lignin (r = −0.86, p < 0.05; r = −0.95, p < 0.01, respectively). The estimated maximum fractional rate of substrate digestion in the second phase (Rm2) showed a strong inverse relationship with lignin (r = −0.93, p < 0.01) in millet but not in sorghum. On the other hand, the time at which the rate of fermentation reached its maximum in phase 1 (tmax1) was negatively correlated with ADF and lignin (r = −0.88, p < 0.05 and r = −0.87, p < 0.05, respectively) in sorghum, whereas in millet only tmax2 (phase 2) was negatively correlated with lignin (r = −0.88, p < 0.05). Estimated differences in the contribution from the different phases to similar cumulative gas at 48 h in stems of different sorghum genotypes indicate the need to complement measurements of total gas production with selected kinetics parameters. The degree of variability between genotypes observed for kinetics parameters related to both, phases 1 and 2 suggest that these parameters have potential for discriminating feed quality differences between crop residues or plant parts. These results point out the difficulty in finding a single feed quality parameter to be used to rank different crop residues of different genotypes. Additional studies are needed to associate these parameters with voluntary intake and in vivo rumen outflow rates with which these phases could be associated

Population Improvement of Pearl Millet and Sorghum: Current Research, Impact and Issues for Implementation

Populations o f pearl millet and sorghum are being developed and improved fo r a variety o f purposes. In this paper, we present a global review o f current populations, their composition, and methods for improvement. The potential impact o f these programs is indicated by recent results regarding responses to recurrent selection and the linkages ofpopulation improvement with development o f lines and varieties in these two crops. Recent research on generating interpool populations and modeling responses to alternative recurrent selection methods are presented fo r population improvement o f pearl millet

Inheritance of Vegetative Growth Index and Related Traits in Pearl Millet

Growth index (GI) is a measure of plant dry weight produced per unit of land area per day (grams per square meter per day). The objective of this study was to elucidate the inheritance pattern of GI for pearl millet [Pennisetum glaucum (L.) R. Br.]. A generation means analysis was conducted to determine the relative importance of additive, dominance, heterotic, and additive × additive epistatic genetic effects for GI. Two elite open-pollinated and three landrace varieties of pearl millet were mated, and the parents, parent selfed, F1s, F1s selfed, and F1s randomated were evaluated in 1990 and 1991 at the International Crops Research Institute for the Semi-Arid Tropics, near Hyderabad, India. Traits measured were GI at 10 d after bloom date (GI1) and at maturity (GI2), bloom date, biomass, harvest index, and plant height. The fully fitted genetic model for the generation means explained from 88 to 95% of the variation among the generations sum of squares for the various traits. Additive effects accounted for the largest proportion of the variation among generation means for all traits except GI2 and biomass, where additive × additive epistatic effects were of greatest importance. Even though inheritance patterns for GI1 and GI2 were dissimilar, a breeding method that emphasizes selection for additive genetic effects should be suitable for improving them

“An Be Jigi”: Collective cooking, whole grains, and technology transfer in Mali

This paper addresses how available resources, food security, technology, and culture are shaping the choices rural Malian women are making to ensure the health, energy, and well-being of their families. This research contributed to evaluating an eight-year research project (An Be Jigi) targeting improved nutrition. The study, performed over four months, used semi-structured interviews of 120 women in six villages in Mali to assess the identified issues with qualitative and quantitative approaches. This paper describes the history of the An Be Jigi project, whole-grain processing techniques, and group cooking for knowledge sharing with rural women for improved nutrition. Interviews revealed substantial adoption of whole-grain processing techniques and women’s appreciation of the nutritional benefits of those techniques. The women engaged in group cooking (cuisines collectives) appreciated the activities and mentioned multiple benefits from using them. Women identified access to mills, and to some extent the social stigma of laziness and poverty associated with whole-grain food, as limiting factors of adoption. This study of women’s practices and perceptions regarding use of whole grain tells a story of changing consumption habits being shaped by culture, technology, knowledge, and available resources. Malian women are agents of change and care in their adoption of new techniques and recipes for the improved nutrition of young children and households

Heterosis in landrace-based topcross hybrids of pearl millet across arid environments

This study quantified the magnitude of heterosis in pearl millet (Pennisetum glaucum) topcross hybrids produced by crossing 16 diverse landraces and three high yielding open-pollinating varieties on two homozygous male-sterile lines. Hybrids and pollinators were grown in 12 year ×;location combinations in India that were grouped into three zones. Genetic components of variance quantifying the differences among these hybrids were estimated. The hybrids showed a conspicuous heterosis for grain yield, earliness and biomass yield but not for straw yield. The level and direction of heterosis for time to flowering depended strongly on the earliness of the male-sterile line. In the terminal drought stress zone hybrids made on the early maturing male-sterile line 843A had the highest level of heterosis for grain yield (88%). This was partly due to escape from terminal stress. In the other two zones the heterosis for grain yield was on average 30%. Heterosis for biomass yield and biomass yield per day was on average also positive in all three zones. For all traits, except time to flowering and biomass yield per day, pollinator effects were the only significant source of variation. Differences between hybrids were mostly caused by additive genetic effects. Significant amount of heterosis observed in landrace-based topcross hybrids for grain yield and other productivity-related traits suggested that substantial improvement in pearl millet productivity in and environments can be obtained by topcrossing locally adapted landraces on suitable male-sterile lines

Seedling survival of abiotic stress: Sorghum and pearl millet

This paper reviews the responses o f sorghum and pearl millet seedlings to abiotic stress and considers the implications for crop production, particularly with respect to the arid and semi-arid tropics. The growing season in much o f this area is characterized by high temperatures, high evaporative demand, unreliable and irregular rainfall, and soils o f poor structure, low fertility, and low water-holding capacity.. Poor seedbed preparation and inadequate sowing methods can increase the likelihood o f abiotic stresses developing. Such conditions result in reduced seedling growth rates/ injury, and ultimately mortality during the germination and seedling emergence stages. The wide range o f causes o f stand failure means there is no single solution. For a given target environment it is necessary to define the reasons for a stand establishment problem and to understand the requirements o f the farmer. Genetic variation for seedling stress tolerance, however, has been shown to exist in both sorghum andpearl millet. Screening techniques have been developed and used in population improvement programs and in identification o f molecular markers linked to the thermotolerance trait. Potential thus exists fo r the genetic improvement o f these crops for survival o f abiotic stresses to complement solutions brought about by changes in agronomic practice

Phosphorus uptake and use efficiency of diverse West and Central African sorghum genotypes under field conditions in Mali

Aims Sorghum [Sorghum bicolor (L.) Moench], a staple crop in West and Central Africa (WCA), is mostly cultivated on soils with low phosphorus (P) availability and thus adaptation to those conditions is vital for food security. Assessment of genotypic variation of WCA sorghum for P uptake and P use efficiency is undertaken to understand the diversity available and opportunities for its use. Method We assessed mature plant yield, P uptake and P use efficiency traits of 70 diverse WCA sorghum genotypes under –P (no P fertilization) and + P field conditions in Mali in 2010, to discover differences among all genotypes tested and between and within specific genotype groups. Results Large significant genotypic variation for P uptake and P use efficiency traits were observed for all genotypes among and within landrace and researcher bred pools under –P conditions. P uptake traits had a larger genotypic variation than P use efficiency traits. Landrace genotypes showed generally higher P uptake and grain P concentration while formally bred genotypes exhibited a higher P use efficiency. Photoperiod sensitivity was related to higher P uptake. Conclusion Genotypic selection for P uptake and P use efficiency traits to improve adaptation to low P soils is possible in sorghum. Use and further study of WCA sorghums for adaptation to low P availability is appropriate as this germplasm shows large variation for P uptake and use efficiency and higher levels of P use efficiency than other important cereals

Stover quality of dual-purpose sorghums: genetic and environmental sources of variation

Improvement of the nutritive value of dual-purpose sorghum (Sorghum bicolor) stover is an important objective for the semiarid tropics where sorghum crop residue is extensively used for livestock feed. To identify the relative importance of genetic and environmental sources of variation for nutritive value, leaves and stems of six diverse dual-purpose sorghum cultivars (M 35-1, Local Yellow, CSV 15, ICSV 735, ICSV 89057 and ICSV 700) were evaluated for in vitro gas production (Gas48hr), neutral detergent fibre (NDF), acid detergent fibre (ADF), lignin, nitrogen, and ash contents under two fertility and two plant density regimes in a field experiment during 2 years (1995 and 1996) in Andhra Pradesh, India. Substantial genotypic differences were observed for stem Gas48hr (25.7 to 33.0 ml in 200 g-1 dry matter (DM)) and NDF (564-687) content. Gas48hr and NDF content of stems exhibited more promise as selection criteria than those of leaves, as stems showed larger portion of variation attributed to genotypes, relatively less genotype by environment (GE) interactions, and were closely related to whole-plant values. Year, nitrogen fertilization and plant density showed very little influence of Gas48hr, NDF or ADF of leaves and stems. Gas48hr exhibited substantial GE interactions with all environmental factors, indicating the need for multi-environment testing to achieve progress