ICAR Research Complex for Eastern Region, Patna, Bihar, 800014, India.
ICAR-Indian Institute of Pulses Research, Kanpur, Uttar Pradesh, 208024, India.
Environ Sci Pollut Res Int. 2019 Oct;26(28):29409-29423. doi: 10.1007/s11356-019-06063-4. Epub 2019 Aug 10.
Rice fallow, a rainfed lowland agro-ecology, is presently gaining particular attention for sustainable cropping intensification in the South Asia. Nevertheless, cropping intensification of rice-fallow areas is largely challenged by non-availability of irrigation, the poor financial status of farmers and soil constraints. Indeed, fast depletion of the soil residual moisture remains the primary obstacle for growing a crop in succession in rice fallows. A field investigation was carried out to identify the most adaptable rice-winter crop rotation and to customize appropriate crop establishment practice for a winter crop that could conserve the soil moisture. Treatments comprised of three crop establishment practices for winter crops [utera (relay cropping, i.e. broadcasting of seeds in standing rice crop 15 days before harvesting), zero tillage (ZT) and ZT with mulching (ZTM)], and five post-rainy-season crops (lentil, chickpea, lathyrus, mustard and linseed). Results showed that lathyrus and lentil could be the potential winter crop in the rice-fallow condition of Eastern India. Except for mustard crop, the productivity of all the winter crops was higher in utera cropping, which was primarily attributed to early crop growth and higher soil moisture content over ZT and ZTM treatments. The higher water use efficiency was recorded under utera cropping over ZT and ZTM treatments. Higher system productivity (system rice equivalent yield) in rice-utera lathyrus (9.3 t ha) and rice-utera lentil (8.1 t ha) led to higher net returns and production efficiency over other treatments (winter crop × crop establishment practice). Benefits of rice residue mulching were prominent in lentil, mustard and linseed crop productivity. Energy use efficiency of different crop establishment practices follows the trend of utera > ZT > ZTM (p < 0.05), being highest in rice-utera lathyrus (5.3) followed by rice-utera lentil (4.8) crop rotations. The simulated data shows that winter crops grown under utera led to less emission of greenhouse gas (GHG) and low global warming potential (GWP) as compared to ZT and ZTM treatments. Rice-lathyrus, rice-lentil and rice-chickpea systems had lower NO emission than rice-mustard and rice-linseed rotations. Hence, lathyrus and lentil could be included in rice fallows ideally with utera for sustainable cropping intensification and improving the farmers' income in Eastern India.
水稻休闲，一种雨养低地农业生态系统，目前在南亚地区得到了特别关注，以实现可持续的作物集约化种植。然而，水稻休闲地区的作物集约化种植在很大程度上面临着缺乏灌溉、农民财政状况不佳和土壤限制等挑战。事实上，快速耗尽土壤残留水分仍然是在水稻休闲地上连续种植作物的主要障碍。进行了一项田间调查，以确定最适应的水稻-冬季作物轮作，并为冬季作物制定适当的种植实践，以保持土壤水分。处理措施包括冬季作物的三种种植实践[间作（即收获前 15 天在水稻作物中广播种子）、免耕（ZT）和免耕覆盖（ZTM）]和五种雨季后作物（豌豆、鹰嘴豆、野豌豆、芥菜和亚麻籽）。结果表明，野豌豆和豌豆可能是印度东部水稻休闲条件下的潜在冬季作物。除芥菜作物外，所有冬季作物的生产力在间作中都较高，这主要归因于间作中的早期作物生长和较高的土壤水分含量，优于 ZT 和 ZTM 处理。间作中的水分利用效率高于 ZT 和 ZTM 处理。水稻-间作野豌豆（9.3 t/ha）和水稻-间作豌豆（8.1 t/ha）的系统生产力（水稻当量产量）较高，导致净收益和生产效率高于其他处理（冬季作物×种植实践）。水稻残茬覆盖的好处在豌豆、芥菜和亚麻籽作物生产力方面表现突出。不同种植实践的能源利用效率遵循间作>ZT>ZTM 的趋势（p<0.05），在水稻-间作野豌豆（5.3）和水稻-间作豌豆（4.8）轮作中最高。模拟数据显示，与 ZT 和 ZTM 处理相比，间作下种植的冬季作物温室气体（GHG）排放较少，全球变暖潜势（GWP）较低。水稻-野豌豆、水稻-豌豆和水稻-鹰嘴豆系统的一氧化二氮排放量低于水稻-芥菜和水稻-亚麻籽轮作。因此，野豌豆和豌豆可以理想地与间作一起用于水稻休闲，以实现可持续的作物集约化种植，并提高印度东部农民的收入。
