Research progress on the mechanism of improving peanut yield by single-seed precision sowing

The contradiction between the supply and demand of edible vegetable oil in China is prominent,and the self-sufficiency rate is less than 35%.Peanut has a very outstanding status in ensuring the security of edible oil and food.The emphasis of increasing peanut yield should be the improvement of pod yield per unit area,because the total yield of peanut has not increased as required.This is attributed to mainly two factors-low increase in the crop productivity and the competition for land for grain and cotton crops.For traditional double-seed sowing pattern,it is difficult to further increase the peanut yield due to the serious contradiction between populations and individuals and the declining population quality under high-yield conditions.Single-seed precision sowing was proven to be a new way to increase the economic coefficient(economic yield/biological yield)with the basic stability of the total biomass,which could make plants distribute evenly,reduce the competition among individuals and attain the full production potential of single plant.In order to reveal the mechanism of increasing peanut yield by single-seed precision sowing,the effects on the ontogenetic development(plant character,physiological characteristic and nutrient utilization)and population structure(population uniformity and photosynthesis,source-sink relationship and yield composition)were systematically expounded.This study reports establishment of the high-yield cultivation technology system with the key technology of single-seed precision sowing and the supporting technology of fertilizing and management.We anticipate its wider application for the improvement of peanut yield.

Design and test of an inside-filling pneumatic precision centralized seed-metering device for rapeseed

The pneumatic precision seed-metering devices used in combination with negative air pressure to suck seed and positive air flow to drop seed could overcome the problem of rapeseed precision planting.However,these devices can only plant a single row at a time or need high airflow pressure,which complicates the seed-metering system and the seeder structure,deteriorate the working reliability and have high power consumption.To overcome above shortcomings,a novel prototype of pneumatic precision centralized seed-metering device with seed inside-filling,sowing six rows at a time,was developed.The main structure and working principle of the prototype were described and the technical parameters were given.Experiments were conducted to investigate the influences of positive pressure,negative pressure,and rotating speed on the seeding performance.The stability of each row and the consistency between all rows associated with the seeding precision were analyzed to evaluate the performance of the prototype.The results indicated that the prototype can meet the requirements of precision seeding and the seed keep intact without any obvious damage.The performance of the prototype was no significant difference when the positive pressure was fluctuated from 200 Pa to 1200 Pa.The best seeding precision parameters in one row of the prototype was 92.48%of the qualified seeding index(Iqs)and 2.55%of the miss-seeding index(Imiss),when the rotating speed was 16 r/min,the positive pressure was 200 Pa and the negative pressure was–1600 Pa.When the rotating speed was 16 r/min,the positive pressure was 200 Pa,and the negative pressure was–1400 Pa or–1600 Pa,the Iqs of six rows were above 86.5%,the stability coefficient of variation(CV)of each row were below 4.6%,and the consistency CV were below 0.9%.Further field experiment showed that the rapeseed sowed by the prototype had acceptable seeding precision.The CV of the numbers of rapeseed seedlings in the field of the total and each row were 6.17%and 6.32%respectively.The research confirmed that the inside-filling pneumatic precision centralized seed-metering device satisfied the agronomic requirements of rapeseed planting and can be a reference for the development of precision seed metering devices.

Development and experiment of rice hill-drop drilling machine for dry land based on proportional speed regulation

Rice precision hill-drop drilling technique in dry land uses fixed hill spacing to achieve orderly planting of crops and to attain good ventilating and day-lighting effects in rice fields.The technique is also beneficial in improving root growth and root structure and in increasing lodging resistance.The high-yield record of Xinjiang Production and Construction Corp’s first division for three consecutive years shows that rice precision hill-drop drilling technique in dry land is one of the important directions to developed rice cultivating mechanization technology.To further improve the quality of rice precision hill-drop drilling machine for dry land,a single profiling,electro-hydraulic proportional real-time adjustment of system was developed according to the agronomic requirements.This machine can simultaneously finish various kinds of seedbed leveling,furrowing and seeding operations,as well as soil covering and pressing.Electro-hydraulic proportional speed regulation makes an AMESim simulation test and analyzes the stability and error of hydraulic adjusting planting distance.Bench testing was carried out on the metering device by simultaneously employing high speed photography technology and analyzing the relationship of the high speed of hill distance and seed charge height.Finally,machine trial was completed.The two-year field experiments of Xinjiang Production and Construction Corp showed that when the machine operation speed is 2.8-3.2 km/h,the sowing depth percent of pass is 75%or higher,the qualified rate of row spacing is 80%or more,the pass rate of row spacing is 90%or higher,and the quantity per hill is 75%or higher.This machine met the various indicators of hill sowing quality requirements.