Core Ideas Drip irrigation improved the aerobic rice yield and water savings by 29 and 50%, respectively. The subsurface drip laid out at 0.8 m lateral distance with 1.0 L per hour dripper discharge irrigation system performed better in rice growth, physiology, and yield. Drip irrigation favored the root oxidizing power, canopy photosynthesis, and dry matter partitioning. There is a twofold increase in water productivity of aerobic rice under drip irrigation system. The use of drip irrigation in upland rice (Oryza sativa L.) cultivation is a contemporary water‐saving strategy. However, inadequate evidence is available related to consequential changes in water productivity on rice yield. The effects of distinctive drip irrigation treatments, namely differences in lateral distances (0.6, 0.8, and 1.0 m), dripper discharge rates (0.6 and 1.0 L per hour, Lph), irrigation methods (surface and subsurface), and the conventional aerobic rice production system (control) on, physiology and water productivity of rice were studied during the summer of 2012 and 2013. Grain yield significantly increased in the subsurface drip irrigation method laid out at 0.8 m lateral distance and in 1.0 Lph discharge rate (5389 kg ha−1) compared with control irrigation method (4181 kg ha−1). This treatment mounts up dry matter partitioning, leaf photosynthesis as well as root oxidizing power. In addition, drip irrigation in aerobic rice production system had twice the water productivity and stimulates longer roots with higher density compared with control irrigation method. The subsurface drip irrigation system with drippers/laterals of 0.8‐m distance with flow rate 1.0 Lph, in aerobic rice production system is a cost‐effective method and had the potential to save water (27.0%) without compromising grain yield in comparison to control irrigation method. This could be the promising technology to be recommended for aerobic rice production system.

A field demonstration trial comparing the growth status, yield ability and water use efficiency of drought-tolerant rice (Oryza sativa L.) varieties and normal paddy rice variety under drip irrigation and paddy irrigation was carried out for two years in Shanghai, China. Under drip irrigation, both inbred and hybrid water-saving and drought resistant rice (WDR) varieties showed better yield capacity than paddy rice varieties tested. WDR varieties under drip irrigation attained more than 95% of the yield level that is achieved in paddy field, while the paddy varieties under the same drip condition reached only about 75%.The methane gas emission was obviously decreased under drip irrigation condition, while the emission of other greenhouse gas like nitrous oxide or carbon dioxide was not observed significant difference between drip and paddy irrigation. It could be concluded that it is practicable to grow water saving and drought resistant rice through drip irrigation. Drip irrigation maintained a competitive grain yield and water productivity, and greatly reduced pollution risk to the environment. Considering the conservative amount of fertilizer application, less than the amount of fertilization in normal paddy field, the yield potential of rice could be improved by increasing the amount of fertilizer as top application in drip irrigation system.

One of the challenges in developing plant-beneficial bacterial agents for agricultural application is ensuring that an effective selection and screening procedure is in place. The sporadic success of using bacterial agents in the field is usually due to the inability of added bacteria to compete with the local microorganisms. In the present study, the effectiveness of Paenibacillus dendritiformis, a unique pattern-forming, Gram-positive, soil bacterium, to reduce disease indices and increase yield in potato crops was examined. This bacterium was chosen as a potential agent based on genome analysis carried out in previous studies. In vitro laboratory experiments, as well as three greenhouse and one field experiment, were conducted. The results show that, in agreement with the hypothesis, P. dendritiformis significantly reduced the maceration area of tuber slices infected by Pectobacterium carotovorum subsp. carotovorum, significantly reduced disease indices in greenhouse experiments and significantly increased tuber yield of infected plants in the field. This work demonstrates the potential of preliminary screening based on genome analysis to identify effective biocontrol agents.

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Background: Rice farming faces major challenges, including water limitation, drought and climate change in the current scenario of agriculture. Among the innovative water-saving techniques, drip irrigation is a forerunner, with maximized water-saving potential, increased grain yield and methane mitigation. Methods: A field experiment was conducted comprising four different drip irrigation practices: (i) sub-surface drip irrigation (SDI) with 1.0 litre per hour (lph) discharge rate emitters (DRE) (SDI+1.0 lph DRE) (ii) SDI+0.6 lph DRE, (iii) surface drip irrigation (DI) with 1.0 lph discharge rate emitters (DI+1.0 lph DRE), (iv) DI+0.6 lph DRE and were compared with (v) a conventional flood aerobic irrigation (considered conventional). Results: The estimated grain yield of rice was found to be 23.5%, 20.3%, and 15.1% higher under SDI+1.0 lph DRE, SDI+0.6 lph DRE and DI+1.0 lph DRE practices, respectively, than the conventional method. A water saving of 23.3% was also observed for all drip practices compared with conventional practices. Seasonal methane emission flux declined 78.0% in the drip methods over the conventional irrigation: better mitigation than previously reported values (alternate wetting and drying (47.5%) and system of rice intensification (29.0%) practices). Continuous soil aeration and enhanced soil methanotrophs (P<0.05) limit the peak methane emission in rice during the flowering phase in drip irrigation, which is reflected in the methane emission flux values. Consequently, the equivalent CO2 (CO2-eq) emissions and yield-scaled CO2 eq-emission were found to be significantly lower in SDI (43.8% and 49.5%, respectively), and DI (25.1% and 26.7%, respectively) methods as compared with the conventional that ensures better methane mitigation and future climate-smart rice production systems. Conclusions: Drip irrigation could reduce the cumulative methane emission in aerobically grown rice. SDI + 1.0 lph DRE practice can be applied in areas with inadequate water availability and effective in reducing the CO2-eq emission with better yield than conventional.