Sustainability indices of agricultural practices so far are developed independent of climatic effects. Especially under dry farming, the effect of rainfall is so overwhelming on the crop performance that this factor cannot be ignored while assessing for sustainability. In view of this, any sustainability index should be made independent of rainfall effect. Hence, a statistical measure of sustainability index 'eta', which is a function of estimate of error 'sigma' derived from a regression of yield through rainfall was developed. The 'eta' is a ratio between difference of mean and standard error (detrended for rainfall) to the maximum recorded yield during the period. Thus the limits of 'eta' are -1 to +1. The proposed procedure was utilized to arrive at sustainable practices from the data of All India Coordinated Research Project for Dryland Agriculture (India) field experiments conducted at both research station and on-farm from varying agroclimatic regions. The practices exceeding a sustainability yield index of 0.67 were considered as suitable for recommendation. The study indicated that barley, pearl millet, mustard, green gram, moth bean and cowpea had a moderate sustainability in arid conditions. Pearl millet at Akola (Maharashtra), pigeonpea and soybean at Indore (Madhya Pradesh) under wet semiarid conditions, and maize and horse gram at Arjia under dry semiarid conditions attained a moderate sustainability. Black gram, lentil and chickpea at Rewa (Madhya Pradesh), and lentil at Varanasi (Uttar Pradesh) also had moderate sustainability under dry subhumid conditions. A classification of superior genotypes of crops based on yield and sustainability and their variation under different climatic situations was made for cereals, pulses, oilseeds and vegetable and other crops. A grouping has also been made based on the variation of yield. Sustainability under different soils and climates and superior genotypes are identified. Some of the highly sustainable genotypes were Vandana of rice at Faizabad (Uttar Pradesh), RR-347-167 of rice at Ranchi, HUR-1095 of rice at Varanasi, BAU-2K-15 of linseed at Ranchi (Bihar), local variety of linseed at Rewa, AT-81 variety of sesame at Rajkot (Gujarat), HG-563 variety of cluster bean at Hisar (Haryana), S-1635 variety of mulberry at Bijapur (Karnataka) and SH-5 of sunn hemp at Hisar.
