Appraisal of Local Farmers’ Practices on Land Management for a Guideline of Agricultural Development in the Sahel Zone of Niger

In order to bridge a gap between research results and farmers’ needs for agricultural development in the Sahel, we made a study of traditional agricultural production systems derived from what we understood about indigenous knowledge (IK) of Sahelian farmers. The study was conducted in the western part of Niger, West Africa. IK was gathered from interviews among several villages of different generations. Then impartiality was verified. We obtained detailed information on land management and topographical features of farmland and devised a thorough local classification system. Statistical results showed that the obtained information was not significantly different among villages and generations. This result brought recognition that IK was a shared knowledge among local farmers in the study area. The study classified in detail a farmland that was directly or indirectly affected by household economy, the potential of natural resources like organic matter, and the relationship between agriculturalist and pastoralist. Understanding this context for soil fertility management at the village level makes it possible to assess the situation more appropriately than simply looking at actual practices, thereby helping to identify a problematic issue that concerns local farmers

Estimation of Drug-effect in Use of Multi-tracer Autoradioqraphy - Effect of S-Adenosyl-L-Methionoie on Postischemic Brain Injury in Rat -

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Response Of The Pigeonpea (Cajanus Cajan (L.) Millspaugh) To Nitrogen Application And Temporary Waterlogging

Short-duration pigeonpea (Cajanus cajan (L.) Millspaugh, cv. ICPL 87)) responded to applied N by increasing its shoot and rwt growth in a Vertisol field at ICRISAT Center in India. However. growth of shoot and roots was impaired and N concentration in leaf was decreased by short-ten (three days) waterlogging. During the recovery phase pigeonpa developed new adventitious rwts around the base of tap root with new nodules. Therefore waterlogged pigeonpea had higher total nodule activity than control plants and there were no differences in N concentration in ieaf at 40 days after the termination of waterlogging

Rooting Behavior Of Intercropped Pigeonpea (Cajanus Cajan (L.) Millspaugh) And Sorghum (Sorghum Bicolor (L.) Moench)

The motlng pmnk of lndhrldual plgeonpea and sorghum plants were compared In monocmpplng and Intercmpplng, under different planting densltles, by use of a slmple dmulatlon appmach. Plgeonpea dld not show any characteristic advantages of root development over sorghum, pmbably due to the presence of a hard stony layer below 30 cm whlch consequently conflned roo1 pmllferatlon wlthln the sutfam layer of 8011. The rootlng depth was unaffected by the cropplng pattern. The root pmllfetatlon near the plant base Increased wlth plant age and was severely reduced by lntercmpplng In case of plgeonpea The lntercmpped sorghum had less mots lnltlally but attained a slmllar denslty as monocmpped sorghum at later stages. It Is demonstrated that root development Is conslderably affected by the planting denslty

Photoelectric Emission from Interstellar Dust: Grain Charging and Gas Heating

We model the photoelectric emission from and charging of interstellar dust and obtain photoelectric gas heating efficiencies as a function of grain size and the relevant ambient conditions. Using realistic grain size distributions, we evaluate the net gas heating rate for various interstellar environments, and find less heating for dense regions characterized by R_V=5.5 than for diffuse regions with R_V=3.1. We provide fitting functions which reproduce our numerical results for photoelectric heating and recombination cooling for a wide range of interstellar conditions. In a separate paper we will examine the implications of these results for the thermal structure of the interstellar medium. Finally, we investigate the potential importance of photoelectric heating in H II regions, including the warm ionized medium. We find that photoelectric heating could be comparable to or exceed heating due to photoionization of H for high ratios of the radiation intensity to the gas density. We also find that photoelectric heating by dust can account for the observed variation of temperature with distance from the galactic midplane in the warm ionized medium.Comment: 50 pages, including 18 figures; corrected title and abstract field

Response of short-duration pigeonpea to nitrogen application after short-term waterlogging on a Vertisol

Short-duration pigeonpea suffers from waterlogging damage following heavy rainfall at the pre-flowering stage on soils with high clay content, such as Vertisols. Effects of short-term waterlogging (3 d) on shoot and root growth of short-duration pigeonpea grown on a Vertisol field were quantified, and the alleviation of waterlogging damage by top-dressing of nitrogen fertilizer was examined. Reduced leaf chlorophyll, increased senescence and abscission of lower leaves were observed within 3 d of the initiation of waterlogging. Root growth and symbiotic N2 fixation were also severely impaired. Root distributions of waterlogged plants were shallower than those of the control during the subsequent recovery period because new adventitious roots were formed in the shallow rather than deep soil layer. Yield of waterlogged crops was significantly smaller than the control. Top-dressing of nitrogen at one day after the termination of waterlogging alleviated waterlogging damage either completely or partially. Leaf chlorophyll and shoot dry mass of waterlogged plants were 78 and 84% of the values in control plants immediately after waterlogging but recovered to 92 and 98% of the control values at the pod-filling stage with a top-dressing of 50 kg N ha−1. Nitrogen application promoted root growth in the shallow soil layers during the first 11 d after application, and in the deeper soil layers during the subsequent 16 d. Total nodule activity was significantly reduced by 100 kg N ha−1, but increased by 50 kg N ha−1 around one month after the top-dressing. The reduction in seed yield was largely compensated for by 50 kg N ha−1, because of recovery from waterlogging damage to shoot and root growth involving increased nodule activity