What are the effects of rice lodging on yield and rice quality? How to prevent it?

Rice lodging refers to the phenomenon that crops growing upright are skewed or even the whole plant falls to the ground due to the influence of natural factors or external forces such as wind and hail and torrential rain. Lodging can reduce the yield and quality of crops and make it difficult to harvest. What are the effects of rice lodging on yield and rice quality? How to prevent it?

1. What are the effects of rice lodging on yield and rice quality?

Many articles have analyzed the effect of rice lodging on yield, explained several major causes and lodging types of rice lodging, and rarely talked about the effect on rice quality.

1. The effect of lodging on yield.

After lodging, the empty shell rate increased, the green head increased, and the yield decreased. From the component factors of yield, lodging mainly caused a significant decrease in seed setting rate and 1000-grain weight, in which seed setting rate had a greater effect on yield.

2. Effect of lodging on rice quality.

When rice lodging, the milled rice rate decreased significantly, and the earlier the lodging, the greater the decrease, and the head rice rate decreased more. At the same time, the effect of lodging on rice quality was omni-directional. After lodging, most of the quality indexes of rice quality (amylose content, gel consistency, etc.) decreased in varying degrees.

The selected green head, chalky grain, chalky grain percentage and chalkiness degree increased significantly.

In addition, the appearance quality may have little effect on the grain length, grain width and the ratio of length to width, but the chalky grain rate and chalkiness degree are hard, and the processed rice has to go through color selection, and the remaining head rice rate is miserable.

The above cognition can be proved by data. Some studies used mid-maturing two-line hybrid rice Liangyoupeijiu and mid-maturing japonica rice CY6 as materials to carry out lodging treatment at different filling stages. The results showed that when lodging occurred 1 day earlier in fruiting stage, CY6 and Liangyoupeijiu caused 2.71% and 2.66% yield loss respectively, reduced seed setting rate by 1.8% and 2.1%, and reduced 1000-grain weight by 0.32 and 0.27g. The milled rice rate decreased by 0.097% and 0.155%, the chalky grain rate increased by 0.13% and 0.27%, the protein content increased by 0.021% and 0.024%, and the eating quality of rice was reduced.

In addition, there is a survey of japonica rice varieties planted in Heilongjiang Province from 1990 to 2010, which draws a conclusion: lodging reduces yield by 35-50% in milk-ripe stage, and rice is all inferior rice; lodging in wax-ripe stage reduces yield by 10-15%, 1000-grain weight decreases by 1.2-2.5%, and chalkiness increases.

Therefore, ensuring that rice does not lodge is a prerequisite for rice to obtain high yield and good quality. So how to prevent lodging?

Second, how to prevent rice lodging?

1. Scientific fertilization

When planting high-quality rice, it is generally recommended not to apply urea, but to correct the old habit of applying more urea because urea is cheap. applying more nitrogen fertilizer is easy to make the seedlings grow vigorously and weaken the lodging resistance and disease resistance of plants. It is suggested that compound fertilizer should be used as the main topdressing fertilizer at the base fertilizer and tillering stage, silicon and zinc fertilizer should be applied at the tillering stage to enhance the stress resistance of rice plants, and potassium fertilizer (15-20 jin) should be applied again after rewatering in the field. From flowering stage to filling stage, potassium dihydrogen phosphate or foliar fertilizer containing amino acid (humic acid) can be sprayed to control diseases and insect pests, the rice is fuller and the rice quality is better.

In order to resist lodging, rice must pay attention to safe fertilization, nutrition balance and formula application according to the law of rice fertilizer requirement.

2. Select varieties with strong lodging resistance.

The selection of high quality rice varieties with strong lodging resistance is helpful to prevent or reduce the degree of lodging. There are almost no such varieties with good rice quality, strong lodging resistance and high yield, but the ones with good rice quality, good lodging resistance and stable yield can be selected, and the overall benefit is better than that of ordinary super rice. For the varieties with excellent rice quality, the yield is mostly average, and the lodging resistance is not strong, so it is suggested to strengthen the management of water and fertilizer.

3. pay attention to the prevention and control of diseases and insect pests

In recent years, there have been a lot of lodging caused by diseases and insect pests and weather reasons. I remember that last year, farmers encountered bacterial leaf streak for the first time and did not know how to control it (some people said that it did not affect the yield or misdispensing prevention and control, and the method of dispensing drugs was wrong). In the fruiting period, because of rainy days and strong winds, it was easy to lodge, and the leaf streak affected the photosynthesis of rice leaves, resulting in a serious reduction in yield. The rice stem borer has suffered serious damage in recent years, and there have been large outbreaks of rice planthoppers in the past, which are easy to make the seedlings lodge. For specific medication, please refer to the small class of rice knowledge and consult the local agrotechnical service personnel.