Real-time adaptive irrigation scheduling under a limited water supply

The problem of real-time irrigation scheduling under limited water supply is considered. The goal is to develop an irrigation operation policy which maximizes crop yields and is responsive to current season changes in weather and other variables. Because irrigation decisions are sequential and dependent on crop and soil water status, and also because crop yields can only be known at the end of the season, the decisions are arrived at by a two-stage process. In the first or the design stage, irrigations are planned for the entire season at weekly intervals using historical data and an optimal irrigation scheduling model. In the second stage, the decisions for the subsequent weeks are revised each week after updating the status of the system with real time data up to that week and solving the irrigation optimization model once again for the new conditions. Thus, each week an irrigation decision is made, the entire planning horizon is kept in view. The procedure is illustrated by application to a case study.     

Comparative Morphological Studies of Microspore Derived and F2 Plants Obtained from an Interspecific Rice Hybrid Oryza sativa Linn. ×O. rufipogon Griff.)*

Anther culture of an interspecific rice hybrid from a cross of Oryza sativa× O. rufipogon was attempted. Of the 117 regenerated pollen clones, 56 could survive to maturity. A majority of these were either haploids or doubled haploids and very few turned out to be chromosomal variants. Comparative study of doubled haploids and the seed derived F₂ plants indicate the distinct advantages of anther culture techniques. (1) Androgenic plants, though few in number, showed greater ariation for all the traits with the exception of ear bearing tillers. (2) Predominance of recombinants with wild traits was observed in F₂ segregation. (3) It was possible to recover indica type recombinants among the anther-derived plants with one or two traits introgressed from O. rufipogon. These results suggest the feasibility and utility of anther culture in distant hybridization for incorporation of alien variation into cultivated rice.     

Evaluation of the Food and Agriculture Organization's global school-based nutrition education initiative, Feeding Minds, Fighting Hunger (FMFH), in schools of Hyderabad, India

OBJECTIVE: To assess the efficacy of the Food and Agriculture Organization's global school-based nutrition education initiative, Feeding Minds, Fighting Hunger (FMFH), in improving nutrition-related knowledge levels of schoolchildren. DESIGN: Adopting the cluster randomisation technique, five schools each in experimental and control groups were randomly chosen from the member schools of a voluntary organisation. Repeated measures of knowledge levels were carried out at three points in time to assess pre-, post-intervention and retention of knowledge gained during the intervention. Children from experimental schools were given nutrition education by teachers in the classroom setting using FMFH material. SUBJECTS/SETTINGS: Schoolchildren (n=358 in the control group and n=312 in the experimental group) of grades VIII and IX from schools in Hyderabad, India.Results: The classroom-based intervention resulted in a significant improvement (P<0.01) in nutrition knowledge levels of schoolchildren in the experimental group. Significant improvement in knowledge was also observed in the control group. The effect size indicated that the improvement in knowledge levels of schoolchildren in experimental schools over control schools was medium (d=0.40), indicating the efficacy of the FMFH programme in improving nutrition-related knowledge. No significant decrease (P>0.05) in knowledge levels was observed after 2 months, indicating retention of the knowledge acquired through the intervention. CONCLUSION: The FMFH programme provides an opportunity for schoolchildren to learn more about nutrition through their teachers in a classroom setting if the lesson plans are adapted to the local circumstances. Furthermore, it has the potential to make nutrition education interactive, effective and sustainable.     

Seroprevalence of Toxoplasma gondii antibodies in captive mithuns (Bos frontalis) from India

One hundred and four mithuns from India were tested for serum antibodies to Toxoplasma gondii by modified direct agglutination test. The overall prevalence of T. gondii antibodies in mithun was 28% (95% CI=19-37). Highest (prevalence rate=46, 95% CI=30-62) seroprevalence of T. gondii antibodies was found in mithuns above 3 years of age and lowest (prevalence rate=14, 95% CI=1-27) in mithuns of 6 months-1 year old. No statistically significant difference was observed between male (prevalence rate=23, 95% CI=10-36) and female (prevalence rate=31, 95% CI=20-42) seroprevalences (P=0.53). Significant difference was observed in the seroprevalence of T. gondii antibodies in mithuns of different strains with the highest (48%) seroprevalence recorded in Arunachal and lowest (14%) in Mizoram strain. The seroprevalence was higher in farm located at lower altitude (305 m a.s.l.) than the farm located at higher altitude (2134 m a.s.l.). This is the first serologic survey for T. gondii antibodies performed on mithuns from India.     

Acute and chronic effects of endosulfan on the haemato-immunological and histopathological responses of a threatened freshwater fish, spotted murrel, Channa punctatus

Two experiments, one short-term and one long-term, were conducted to elucidate the acute and chronic effects, respectively, of endosulfan exposure on the haemato-immunological and histopathological responses of Channa puncatatus. In the short-term study, fish were exposed to sublethal endosulfan (8.1 μg l⁻¹) for 12, 24, 36, 48, 72 and 96 h. In the long-term study, fish were fed with normal diet and simultaneously either exposed to endosulfan (1.2 μg l⁻¹) for 90 days or not. Results showed that the ascorbic acid levels in both the liver and the muscle decreased significantly (P < 0.05) by acute and chronic endosulfan exposure. The haemoglobin (Hb) level reduced significantly (P < 0.05) by 15.5% within 12 h of acute endosulfan exposure, further decreased by 25.8% after 24 h of exposure, however, thereafter the values increased and at the end of 72 h returned to normal levels. Almost similar trend was observed for the erythrocyte (RBC) count. The WBC count and the nitroblue tetrazolium (NBT) value showed a general increasing trend with increase in the duration of acute endosulfan exposure. The chronic exposure of C. punctatus to endosulfan significantly (P < 0.05) lowered the Hb level, RBC and WBC counts, NBT reduction value and the plasma parameters such as plasma protein, albumin (A) and globulin (G) compared with that of the control (except for A/G ratio). Endosulfan exposure also severely altered the liver histological structure. Overall results indicated that both short-term acute and long-term chronic endosulfan exposure had a significant impact on the haemato-immunological parameters and tissue histopathology of C. punctatus.     

Resistance to blast (Magnaporthe grisea) in a mini-core collection of finger millet germplasm

Blast caused by Pyricularia grisea [teleomorph: Magnaporthe grisea] is an economically important and widespread disease of finger millet in the world. Host resistance is the most economical and effective means of combating this disease as finger millet is predominantly grown by resource-poor and marginal farmers. At the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), we evaluated a finger millet mini-core collection of 80 germplasm accessions (about 1 % of the total germplasm collection representing major trait variability) for blast resistance both in the field and greenhouse. Field evaluation was done using a refined screening technique that included new improved rating scales for leaf, neck and finger infection. Sixty six of the 80 accessions showed combined resistance to leaf, neck and finger blast in two seasons (2009 and 2010) of field screening. A highly significant and positive correlation was found between neck and finger blast ratings (r?=?0.92), whereas small but significant correlations were found between leaf blast and neck blast (r?=?0.25) and between leaf blast and finger blast (r?=?0.30). These accessions were also screened for leaf blast resistance in the greenhouse by artificial inoculation of seedlings to confirm field observations. Fifty-eight of the 80 accessions were resistant to leaf blast in the greenhouse screen as well. These resistant accessions represented one wild (africana) and four cultivated races (vulgaris, plana, elongate and compacta) of finger millet that originated from 13 countries in Asia and Africa and exhibited considerable diversity for agronomic traits, such as maturity period, plant height and panicle type. These blast resistant accessions from the mini-core collection would be useful in finger millet disease resistance breeding programs.