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Drought is the major abiotic constraint affecting groundnut productivity and quality worldwide. Most breeding programmes in groundnut follow an empirical approach to drought resistance breeding, largely based on kernel yield and traits of local adaptation, resulting in slow progress. Recent advances in the use of easily measurable surrogates for complex physiological traits associated with drought tolerance encouraged breeders to integrate these in their selection schemes. However, there has been no direct comparison of the relative effi ciency of a physiological trait-based selection approach (Tr) vis-à-vis an empirical approach (E) to ascertain the benefi ts of the former. The genetic material used in the present study originated from three common crosses and one institute-specifi c cross from four collaborating institutes in India (total seven crosses). Each institute contributed six genotypes and each followed both the Tr and E selection approaches in each cross. The fi eld trial of all selections, consisting of 192 genotypes (96 each Tr and E selections), was grown in 2000/2001 in a 4 × 48 alpha design in 12 season × location environments in India. The selection effi ciency of Tr relative to E, RE Tr , was estimated using the genetic concept of response to selection. Based on all the 12 environments, the two selection methods performed more or less similarly (RE Tr = 1.045). When the 12 environments were grouped into rainy season and post-rainy season, the relative response to selection in Tr method was higher in the rainy than in the post-rainy season (RE Tr = 1.220 vs 0.657) due to a higher genetic variance, lower G × E, and high h 2 . When the 12 environments were classifi ed into four clusters based on plant extractable soil-water availability, the selection method Tr was superior to E in three of the four clusters (RE Tr = 1.495, 0.612, 1.308, and 1.144) due to an increase in genetic variance and h 2 under Tr in clustered environments. Although the crosses exhibited signifi cant differences for kernel yield, the two methods of selection did not interact signifi cantly with crosses. Both methods contributed more or less equally to the 10 highest-yielding selections (six for E and four for Tr). The six E selections had a higher kernel yield, higher transpiration (T), and nearly equal transpiration effi ciency (TE) and harvest index (HI) relative to four Tr selections. The yield advantage in E selections came largely from greater T, which would likely not be an advantage in water-defi cient environments. From the results of these multi-environment studies, it is evident that Tr method did not show a consistent superiority over E method of drought resistance breeding in producing a higher kernel yield in groundnut. Nonetheless, the integration of physiological traits (or their surrogates) in the selection scheme would be advantageous in selecting genotypes which are more effi cient water utilisers or partitioners of photosynthates into economic yield. New biotechnological tools are being explored to increas...

Gradual depletion of world petroleum reserves and the impact of environmental pollution of increasing exhaust emissions lead to the search for a suitable alternative fuels for diesel engines. The substitution of conventional fuels (gasoline, diesel) by renewable biofuels is considered a potential way to reduce pollution and to support the sustainable development of a country. Direct use of vegetable oil and animal fat is a promising alternative to solve these problems. An exhaustive review of the experiments in this area, carried out by several researchers in last three decades, is presented here. Different problems associated with the direct use of vegetable oil and animal fat and potential solutions from both public and private sectors are discussed. Some engine manufacturers have started to launch full-warranty engines with vegetable oil as fuel. It is expected that the competitive engine market will witness more intense research, resulting in the launch of more vegetable-oil engines with full warranties. The steep rise in food prices in recent years is concerning policy-makers and has raised the old 'food vs fuel' debate. It has been concluded that vegetable oil can probably only substitute small to medium portions of petroleum-based fuel due to future severe land-usage competition from food sector. This calls for intense research initiatives into the production of suitable fuel from non-edible vegetable oil, grown in wasteland. In this regard, genetic engineering may prove to be extremely effective in developing 'designer fuel'.