Mixed‐cropping systems of different rice cultivars have grain yield and quality advantages over mono‐cropping systems

Abstract

BACKGROUND A mixed‐cropping system that enhances farmland biodiversity has the potential to improve grain yield and quality; however, the impacts of growing different rice cultivars simultaneously has been rarely investigated. In the present study, five popular rice cultivars were selected and ten mixture combinations were made according to the growth period, plant height, grain yield and quality, and pest and disease resistance. Seedlings of the five cultivars and ten mixture combinations (mixed‐sowing of the seeds in an equal ratio, then mixed‐transplanting and finally mixed‐harvesting) were grown in plastic pots in a glasshouse during the early and late growing seasons in 2016. RESULTS Compared with the mono‐cropping systems in the early and late growing seasons in 2016 (paired t‐test), the mixed‐cropping systems increased the rice leaf photosynthetic rate, soil plant analysis development (SPAD) index and total aboveground dry weight. Moreover, mixed‐cropping systems improved the number of spikelets per panicle, seed‐setting rate, and grain weight per pot and harvest index by 19.52% and 5.77%, 8.53% and 4.41%, 8.31% and 4.61%, and 10.26% and 6.98% in the early and late growing seasons, respectively. In addition, mixed‐cropping systems reduced chalky rice rate and chalkiness degree by 33.12% and 43.42% and by 30.11% and 48.13% in the early and late growing seasons, respectively. CONCLUSION The SPAD indexes and photosynthetic rates enhanced at physiology maturity in mixed‐cropping systems may result in higher grain yield and better grain quality. In general, it was found that mixed‐cropping with different rice cultivars has the potential for increasing grain yield and improving grain quality. © 2018 Society of Chemical Industry

Food Security in China: A Brief View of Rice Production in Recent 20 Years

“…There were 11,100 rice cultivars released by the country (1641) and provinces (9459) from 2000 to 2019 [ 29 , 30 ], during which agronomic traits and resistance to biotic and abiotic stresses were improved to ensure higher yield potentials. Both the TRP and GPA were significantly correlated with the number of annually released new rice cultivars ( Table 3 ), indicating that the rise of rice production in China is also contributed by the release of new rice cultivars [ 31 , 32 ]. The R coefficient was largest in MRP, suggesting that middle rice production benefited most from the released new rice cultivars.…”

A Scientometric Analysis of Worldwide Intercropping Research Based on Web of Science Database between 1992 and 2020

“…The co-occurrence analysis demonstrates that intercropping studies generally focus on four aspects as indicated by keywords of intercropping/maize, biodiversity/conservation, agroforestry, and carbon, respectively. Given that applications of synthetic fertilizers significantly increased grain yield over the past decades, but overuse of chemical fertilizer leads to soil and environmental pollution and threatens agricultural sustainability [77], more studies are required to develop efficient approaches so as to improve the crop quality while maintaining or increasing yield to meet food security and higher demands of food quality [78][79][80]. As intercropping has been well studied in well-developed countries including the USA and the mostly populated countries including India and China, more intercropping studies in undeveloped countries in Africa should be conducted to fight starvation and malnutrition and to adapt to climate change [63,81].…”

Mixed cropping with duck co‐culture: an agroecological system to improve grain quality and farm profitability

“…reported a mixed‐cropping system produced higher yields than a mono‐cropping in the same area. Li et al 18 . found that mixed cropping using different rice varieties improved grain yield and quality more than mono‐cropping systems did.…”

“…In a previous study, we measured the agronomic characteristics of rice varieties planted in mixed cropping, and those rice varieties were mono‐cropped separately as control. Rice in the mixed‐cropping system displayed relatively high leaf photosynthetic rates, total aboveground biomass levels, and grain appearance quality scores 18 9,29,30 .…”

“…For example, Malézieux et al 17 reported a mixed-cropping system produced higher yields than a mono-cropping in the same area. Li et al 18 found that mixed cropping using different rice varieties improved grain yield and quality more than mono-cropping systems did. Furthermore, Paulsen et al 19 found that mixed-cropping systems reduced pest infestations in winter rape population (Brassica napus) which were co-planted with cereals or legumes, and that they suppressed weed growth among linseed populations (Linum usitatissimum) which were co-planted with wheat (Triticum aestivum) or false flax (Camelina sativa).…”