Application of insect-proof nets in pesticide-free rice creates an altered microclimate and differential agronomic performance

Abstract

BackgroundInsect-proof nets are commonly used in crop production and scientific research because of their environmental, economic, and agronomic benefits. However, insect-proof nets can unintentionally alter the microclimate inside the screenhouse and therefore greatly affect plant growth and yield. To examine the microclimate and agronomic performance of pesticide-free rice under insect-proof nets, two-year field experiments were carried out in 2011 and 2012.MethodsIn the present study, the experiment was conducted by using a split-plot design considering the cultivation environment (open field cultivation (OFC) and insect-proof nets cultivation (IPNC)) as the main plot and the varieties as the subplot (Suxiangjing3 and Nanjing44).ResultsIPNC significantly reduced the air speed and solar radiation, and slightly increased the daytime soil temperature, daytime air temperature, and nighttime relative humidity. By contrast, the nighttime soil temperature, nighttime air temperature, and daytime relative humidity were relatively unaffected. The grain yield of both rice cultivars decreased significantly under IPNC, which was largely attributed to the reduced panicle number. The reduced panicle number was largely associated with the decreased maximum tiller number, which was positively correlated with the tillering rate, time of tillering onset, and tillering cessation for both rice cultivars under IPNC. In addition, dry matter accumulation significantly decreased for both rice cultivars under IPNC, which was mainly caused by the decreased leaf area duration resulting from the reduced leaf area index. By contrast, the mean net assimilation rate was relatively unaffected by IPNC.DiscussionInsect-proof nets altered the microclimate in comparison with OFC by reducing the air speed and changing the radiation regime, which significantly affected dry matter production and yield of both japonica rice cultivars. Our results indicated that cultivation measures that could increase the tillering rate and the maximum tiller number under IPNC would lead to a significant increase in panicle number, ultimately increasing grain yield. In addition, maintaining a high leaf area duration by increasing the leaf area index would be important to compensate for the dry matter accumulation losses under IPNC. These findings are critical to provide a theoretical basis for improving agronomic performance of pesticide-free rice under IPNC.

Microclimatic behavior of a screen house proposed for horticultural production in low-altitude tropical climate conditions

“…SH is widely used in warm and arid Mediterranean climates (Al-Mulla et al, 2008), this technological adaptation of the productive system allows the construction of an enclosure where the cover and the lateral walls are made of insect screens to limit the entry of some pests, to mitigate the negative effect of severe climates, to reduce the water consumption of the plants, to change the spectrum of the solar radiation and the related physiological benefits, as well as to reduce pesticides applications of, and improve the yield and final quality of the crops (Guo et al, 2015; Villagran & Jaramillo 2020Microclimatic behavior of a screen house... Vidogbéna et al, 2015;Teitel et al, 2017;Mahmood et al, 2018;Mupambi et al, 2018;Yang et al, 2018;Alvarado et al, 2020).…”

Enhancement of Ultrasonic Seed Treatment on Yield, Grain Quality Characters, and 2-Acetyl-1-Pyrroline Biosynthesis in Different Fragrant Rice Genotypes

“…The growth period of fragrant rice varieties in the present study was about 120 days, and the microclimate of the paddy field could be complicitly varied across days and months [28]. The study by Yang et al [29] showed that the alteration of microclimate had substantial effects on rice agronomic performance. The responses of yield formation of different fragrant rice genotypes to ultrasonic seed treatment also were slightly different.…”

Lanthanum (La) improves growth, yield formation and 2-acetyl-1-pyrroline biosynthesis in aromatic rice (Oryza sativa L.)

“…In the field, variations in climate especially the sudden occurrence of short-term extreme weather, have substantial effects on rice yield [22]. Moreover, the microclimate in paddy fields which is complicated and difficult to measure, also influences yield formation of rice [23]. A stronger antioxidant system in rice ensures stable rice production stabilization.…”