Rice-wheat {Oryza sativa L-Triticum aestivum L.) rotation is the major production system in Asia, covering about 18 million ha. Conventional practice of growing rice (puddled transplanting) and wheat (conventional till, CT) deteriorate soil physical properties, and are input-and energy-intensive. Zero-tillage (ZT) along with drillseeding have been promoted to overcome these problems. A 7-yr permanent plot study evaluated various tillage and crop establishment (CE) methods on soil physical properties with an aim to improve soil health and resourceuse efficiency. Treatments included transplanting and direct-seeding ot rice on flat and raised beds with or without tillage followed by wheat in CT and ZT soil. Bulk density (D|j) of the 10-to 20-cm soil layer was highest under puddled treatments (1.74-1.77 Mg m"') and lowest under ZT treatments (1.66-1.71 Mg m"'). Likewise, soil penetration resistance (SPR) was highest at the 20-cm depth in puddled treatments (3.46-3.72 MPa) and lowest in ZT treatments (2.51-2.82 MPa). Compared with conventional practice, on average, water-stable aggregates (WSAs) > 0.25 mm were 28% higher in ZT direct-seeding with positive time trend of 4.02% yr~'. Infiltration was higher (0.29-0.40 cm h~') in ZT treatments than puddled treatments (0.18 cm h"'). The least-limiting water range was about double in ZT direct-seeding than that of conventional practice. Gradual improvement in soil physical parameters in ZT system resulted in improvement in wheat yield and is expected to be superior in longrun on system (ricc+wheat) basis. Further research is needed to understand mechanisms and requirements of two cereals with contrasting edaphic requirements in their new environment of ZT direct-seeding.

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Rice (Oryza sativa L.)–wheat (Triticum aestivum L.) is the major cropping system occupying 13.5 million ha in the Indo‐Gangetic Plains of South Asia. Conventional‐tillage practices are resource and cost intensive. A 7‐yr study evaluated six treatments (T) involving three tillage methods and two rice establishment methods on crop yield, water productivity, and economic profitability in a rice–wheat rotation. Average rice yields in the conventional practice of puddling and transplanting without (T1) and with (T2) mid‐season alternate wetting‐drying were highest (7.81–8.10 Mg ha−1) and increased with time (0.26 Mg ha−1 yr−1) in T2. Compared to T1, rice yields in direct drill‐seeding with zero‐tillage averaged 16% lower on flat (T5) and 43% lower in raised beds (T3). Rice yield in raised beds (T3 and T4) decreased with time (0.14–0.45 Mg ha−1 yr−1). Conversely, wheat yielded 18% higher after zero compared to conventional‐tillage. Treatment 2, despite low soil matric potential during vegetative development, had higher water productivity with 25% less water use compared with T1 and 19% less compared with other treatments. Conventional‐tillage and crop establishment practices had higher net cash return in rice but in wheat it was higher with zero‐tillage. Overall, T2 and T5 had the highest net returns (∼1225US$) and T3 and T4 had the lowest (747–846 US$) in the rice–wheat system. Zero‐tillage on flat beds (T5), however, would conceivably be more sustainable than the conventional T2 in the long‐run. Yields of zero‐tillage with direct‐seeding of rice on flat beds (T5) must improve before adoption occurs.

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Plants are susceptible to phytopathogens, including bacteria, fungi, and viruses, which cause colossal financial shortfalls (pre-and post-harvest) and threaten global food safety. To combat with these phytopathogens, plant possesses two-layer of defense in the form of PAMP-triggered immunity (PTI), or Effectors-triggered immunity (ETI). The understanding of plant-molecular interactions and revolution of high-throughput molecular techniques have opened the door for innovations in developing pathogen-resistant plants. In this context, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) has transformed genome editing (GE) technology and being harnessed for altering the traits. Here we have summarized the complexities of plant immune system and the use of CRISPR-Cas9 to edit the various components of plant immune system to acquire long-lasting resistance in plants against phytopathogens. This review also sheds the light on the limitations of CRISPR-Cas9 system, regulation of CRISPR-Cas9 edited crops and future prospective of this technology.

The production of bioethanol from rice straw can contribute to the rural economy and provide clean fuel in a sustainable manner. However, phenolic compounds, which are mostly produced during acid pretreatment of biomass, act as inhibitors of fermenting microorganisms. Laccase is well known for its ability to oxidize lignin and phenolic compounds derived from lignocellulosic biomass. In the present study, an immobilized enzyme cocktail containing laccase was isevaluated in regard to its ability to enhance the saccharification and fermentation processes by reducing the amount of phenolic compounds produced. Saccharification of rice straw with the laccase‐supplemented immobilized enzyme cocktail reduced phenolic compounds by 73.8%, resulting in a saccharification yield of 84.6%. In addition, improved yeast performance was is noted during the fermentation process, resulting in a 78.3% conversion of sugar into ethanol with an ethanol productivity of 0.478 g/L/h. To the best of our knowledge, this is the first description of the use of an immobilized enzyme cocktail comprised of Celluclast 1.5L, β‐glucosidase, and laccase for the production of bioethanol from rice straw. This study details a potential approach to producing biofuels from agricultural biomass, the applicability of which can be improved through up‐scaling.