Performance of low-input agriculture with ZBNF - A case study on groundnut-wheat cropping system in Saurashtra Region of Gujarat

Low-input agriculture with ZBNF in Groundnut-wheat under Saurashtra region

Abstract

Sustainable low-cost farming in (groundnut based) cropping system(s) offers a much-needed alternative to conventional input-intensive agriculture. Its long-term benefits include maintaining soil quality, increased productivity & return per unit input use, and biodiversity related benefits. Could it be a reality in near future for a low cost natural farming especially in realizing a sustained groundnut production when the crop or its cropping system is mostly input oriented with high cost of cultivation/production? Keeping this in view and finding out an appropriate reply, a field experiment was carried out in a low (soil) fertility medium black calcareous soil with three different farming practices in main plot viz., Natural Farming (NF), Conventional Farming (CF) and Organic Farming (OF) using two cultivars GJG-22 (Virginia Bunch) and TG 37-A (Spanish Bunch) in large sub plot (~1/100^th of a hectare) at ICAR-DGR, Junagadh during kharif 2022-23. The prevailing agro-ecosystem involves an irrigated tract of alkali soil (with pH of 8.24, low available N, P, K, medium SOC of 0.63%) falling under Southern Saurashtra Agro-climatic Zone of Gujarat, and Gujarat Plain and hill region of India. These experimental plots were laid out in 8-times replicated split plot. Further, these permanent plots of three farming practices were cultivated with wheat (two cultivars of wheat viz., GW 451 and Lok 1 were grown) in rotation during rabi (winter season) of 2022-23. These treatments were in fact taken up following a residual exhaustive fodder crops of pearl millet during spring/summer 2021-22 prior to sowing of kharif (rainy season of 2022) crop of groundnut for eliminating soil heterogeneity, if any. The study revealed that pod yield to the tune of 1316- 1630 kg/ha (with a mean minimum of 1473 kg/ha) was realized with low cost natural farming practice depending on the varieties (higher yields with Spanish Bunch) vis-à-vis 1448-1779 kg/ha (with a mean yield of 1613 kg/ha) in organic farming practice. On the contrary, higher pod yield of 1679- 1965 kg/ha (with a mean maximum yield of 1822 kg/ha) was realized with the conventional practice employing improved production technologies (and also higher with Spanish Bunch).  The growth/developmental parameters/values including economics and total system productivity (based on groundnut equivalent yield) were also higher under the treatment. Besides pod yield, the maximum values in respect of groundnut plant attributes viz., haulm yield (2740 kg/ha), total (biological) yield (4562 kg/ha),100-kernel wt. (32.0g in TG 37A and 38.5g in GJG 22 with mean maximum 35.2g), higher shelling per cent (69.2), kernel yield (1259 kg/ha), net return (INR 67267/ha), BCR (1.50), nutrient (NPK) uptake, and its efficiency (NPK uptake/100-kg pod) were evident under conventional farming practice (compared to others). However, the values in respect of certain specific parameters viz., dry wt. of plants (19.0g), pods/plant (14.9), nodule count (174/pl), nodule dry weight (68.7 mg/pl), and HI (42.2%) were maximum either with natural farming or organic farming practices (with an edge over conventional practice) due to their soil-building effect. Similar crop responses were conspicuous in case of the succeeding wheat crop (higher values of the observed parameters with high yielding GW 451). Thus, overall crop response to farming practices keeping in view of observed parameters and groundnut equivalent/total yield/monetary returns were in the order: CF > OF > NF; and the ratio of NPK uptake for realization of higher per unit productivity (across farming practices and varieties) was observed to be 6.8:1.0:2.2 for groundnut and 3.9:1.0:3.3 for wheat. Therefore, it was inferred from the above that although groundnut crop responded to low cost natural farming (with 19% lower yield over CF), yet, conventional farming practice based on integrated nutrient management comprising of chemical fertilizers, FYM and pesticides was advantageous for realizing higher yield/return from both the component crops of groundnut-wheat and the cropping system as a whole. Further efforts are made to realize higher productivity in ecofriendly farming (natural or organic) through reinforcement of nutrient(s) suitably and appropriately.