Research on Obviate Measures of Continuous Cropping Obstacles of Rehmannia Glutionsa
|School||Henan Agricultural University|
|Course||Crop Cultivation and Farming System|
|Keywords||Rehmannia glutinosa Libosch Continuous cropping obstacle reduction technology chlorophyll content root activity biological yield|
Using Rehmannia glutinosa Libosch, a official herb with typical continuous cropping obstacles to do the experiment, adopting the field experiment and lab analysis. The reduction rate of continuous cropping obstacles of Rehmannia glutinosa as the aim, starting from the seedling and transplanting, Achyranthes bidentata rotation and fertilized as green manure, continuous cropping soil treatment those three aspects, to measure chlorophyll, activities of the root tubers, biological yield of its entire growth the growth season, and got the conclusions as follow:(1) In the matter of Rehmannia glutinosa production, using he reduction rate of continuous cropping as the aim, the method of seedling and transplanting showed the greatest result, exogenous addition method on soil treatment came after in order, the Achyranthes bidentata rotation and fertilized as green manure and short-term (1 year) to reduce the effect of continuous cropping obstacles Rehmannia glutinosa was the worst.The seedling and transplanting experiment showed that within 40 days after emergence of seedling, transplanting significantly reduced the continuous cropping obstacles of Rehmannia glutinosa.are. During this period, transplanting with soil 20 days after the emergence of seedling got the highest rate of reduction, it was 76.8%; 40 days after the emergence, transplanting without soil got the lowest rate of reduction, it was 9.27%; transplanting with soil was superior than bare root transplanting. This also proved that continuous cropping obstacles formed in early period of its growth.In the Achyranthes bidentata rotation and fertilizing as green manure experiment, the rotation and whole plant as green manure got the highest rate of reduction, that was 36.06%; the underground part of Achyranthes bidentata as green manure without rotation showed the lowest rate of reduction, that was-23.49%. Achyranthes bidentata rotation showed better result of reducing continuous cropping obstacles of Rehmannia glutinosa than none rotation. In the rotation experiment, the reduction rate of continuous cropping obstacles by using Achyranthes bidentata as green manure in orader was whole plant> underground part> no green manure> overground; None rotation got all negative reduction rates, and even had the trend of increasing continuous cropping obstacles.Adding calcium cyanamide and microbial inoculums to soil both could greatly reduce continuous cropping obstacles, in which adding microbial inoculums showed the best result, and the highest rate of reduction was high as 54.25%; followed by adding calcium cyanamide, the highest rate reduction was 45.47%; And the method of water leaching showed the worst result on reducing continuous cropping obstacles.(2) Different treatments of reduction technology had very different effects on the chlorophyll content. Processed soil treatment had better results than Achyranthes bidentata on chlorophyll content.In the Achyranthes bidentata rotation experiment, the chlorophyll content in Rehmannia glutinosa of none rotation was a little higher than in ones of rotation; using different part of Achyranthes bidentata as green manure, the chlorophyll content showed the curve "high-low-high-low", that was whole plant> underground part> no green manure> overground.In the processed soil experiment, fertilizing by calcium cyanamide had obvious effects on chlorophyll content, comparing with the check it was in turn 183.21%, 253.89% and 14.67% higher. It indicated that addition of calcium cyanamide promoted the photosynthetic system of leaves; adding microbial inoculums and leaching treatment had not got such good results, it was respectively,56.81%,63.39%,—13.41%; the simulation of rain wash had the minimal effect on chlorophyll content in leaves of Rehmannia glutinosa, it increased 20.64%, respectively,4.99%-3.37% respectively.(3) In the Achyranthes bidentata rotation and fertilized as green manure experiment, the root activity of Rehmannia glutinosa appear to increase, in which the overground part as green manure got the maximum incensement and the other parts also increased root activity a little. In the non-rotation treatment, root activity of Rehmannia glutinosa fertilized by green manure was less active than which of the check, it was the lowest by overground part of Achyranthes bidentata as green manure and not obvious by the other parts. Achyranthes bidentata rotation got a significant effect on root activity, fertilizing the whole plant got more significant effect than root activity than fertilizing the other parts.In the processed soil treatment, with decline of addition of calcium cyanamide, the root activity of seedling appeared to be at first increasing and then decreasing. Comparing with the check, it deceased 19.18%, increased 36.2% and 21.22%; with decline of addition of microbial inoculums, it also appeared to be the same trend. Comparing with the check, it increased 13.72%,23.80%3.65% respectively, and each treatment had obvious differences; As decline of times of rain washing, root activity kept increasing, it increased 14.89%,62.21%,81.89%, and each treatment had obvious differences.