Characteristics of Population Quality and Rice Quality of Semi-Waxy japonica Rice Varieties with Different Grain Yields

Abstract

A primary focus of rice breeding and production is the optimization of yield and quality. Currently, semi-waxy japonica rice is widely planted in the middle and lower reaches of the Yangtze River due to its good eating quality and strong reputation among consumers. However, little information is yet available on grain yield formation and rice quality characteristics of these semi-waxy japonica rice varieties with different grain yields. In this study, three high-yielding (HGY) semi-waxy japonica rice varieties and three low-yielding (LGY) semi waxy japonica rice varieties were compared for population quality and rice quality in 2018 and 2019. The average values of spikelet per panicle, 1000-grain weight, and total spikelet number of the HGY varieties were significantly higher than those of the LGY varieties, while the panicle number and filled grain rate showed the opposite. Compared with the LGY varieties, the HGY varieties had a larger leaf area index at each growth stage, with a larger high efficient leaf area composed of a larger leaf length and width and smaller leaf angles of the top three leaves, as well as a greater single stem-sheath weight, more total dry matter accumulation, and longer growth duration from elongating to maturity. There were significant differences in rice quality between the HGY and LGY varieties. Compared with the LGY varieties, the head milled rice rate of the HGY varieties decreased significantly, and the chalky kernel rate and chalkiness degree increased significantly. Due to the low protein content, high peak viscosity, trough viscosity, and final viscosity and breakdown, as well as low setback, consistence, and pasting temperature of the HGY varieties, their taste values were significantly better than those of the LGY varieties. These results suggest that the HGY varieties could achieve a synergistic improvement of grain yield and eating quality, but the milling quality and appearance quality require further improvement.

Effects of Mechanical Transplanting Methods and Planting Geometry on Yield Formation and Canopy Structure of Indica Rice under Rice-Crayfish Rotation

“…The tiller dynamic, leaf area index, and dry matter accumulation of single-stem and population can effectively reflect the population quality at rice key growth stages of [17]. Generally, the formation of a high yield population of transplanted rice is due to the fol-…”

“…The tiller dynamic, leaf area index, and dry matter accumulation of single-stem and population can effectively reflect the population quality at rice key growth stages of [17]. Generally, the formation of a high yield population of transplanted rice is due to the following characteristics: high seedling quality; rapid recovery from transplanting injury and tiller emergence after transplanting; suitable peak seedling quantity; high mid-term leaf area index and photosynthetic material accumulation; and high-quality population with high photosynthetic efficiency at heading stage.…”

Cross-flow fan on multi-dimensional airflow field of air screen cleaning system for rice grain

“…The speed of the small end of the cone observation tube was the average of four measuring points. The air velocity calculation equation for any end surface is Equation (1) [17] .…”

“…Automatic control was used by some scholars in the parameter control of the cleaning system. Through the fuzzy control algorithm under big data, real-time adjustment of multiple parameters is realized to meet the actual working conditions [10,11] . Liang et al [12] developed a fuzzy control system, which can monitor the sieve loss of grains through the monitoring device in the cleaning system.…”

Field Investigation of the Static Friction Characteristics of High-Yielding Rice during Harvest

“…The characteristics of high-yielding rice and ordinary rice are very distinct. For example, the former has a higher unit yield, larger panicles, more grains, denser growth, greener stems, lusher leaves, higher water content, and stronger disease resistance than the latter [18][19][20][21][22]. These characteristics of high-yielding rice significantly impact key processes of traditional rice combine harvesting, including threshing separation, cleaning, and grain transportation.…”