The present invention relates to the field of environmental protection, and in particular to a leaf surface barrier for accurately controlling cadmium absorption and transport related gene expression in rice, and an application thereof. The present invention comprises: reducing a raw material, i.e., selenious acid or selenite, by using ascorbic acid to generate a nanogel, and then emulsifying the nanogel for peptization to obtain a leaf surface barrier for accurately controlling cadmium absorption and transport related gene expression in rice; and then mixing the leaf surface barrier with a silica sol to obtain a composite selenium and silica sol leaf surface barrier. The present invention also provides a leaf surface barricading method for accurately controlling cadmium absorption and transport related gene expression in rice. By applying the leaf surface barrier, the silica sol or the composite selenium and silica sol leaf surface barrier having a particular atomization degree and a particular concentration by means of foliar spray during a particular growth period of rice and within a particular time, the cadmium accumulation in rice can be effectively reduced. Applying the present invention to a moderately or lightly polluted field can enable cadmium content in rice to satisfy the food hygiene standards, and therefore is significant for achieving the safe use of the large area of field polluted by heavy metal cadmium in China.

An integrated eliminating device and its method for initial runoff pollution is provided, wherein a plurality of the water receiving pipes for collecting initial runoff are gathered and connected to the first water reservoir, one end of the water inlet pump is connected with the first water reservoir via the water receiving pipes, and the other end of the intake pump is connected with an water inlet opening of the rice field; the rice field is divided into a plurality of sub-parcels in a shape of long stripes, a regulating gate is set. An outlet of the rice field is communicated with the second water reservoir and which is communicated with the water inlet opening of the rice field via the reflux pump.

An integrated eliminating device and its method for initial runoff pollution is provided, wherein a plurality of the water receiving pipes for collecting initial runoff are gathered and connected to the first water reservoir, one end of the water inlet pump is connected with the first water reservoir via the water receiving pipes, and the other end of the intake pump is connected with an water inlet opening of the rice field; the rice field is divided into a plurality of sub-parcels in a shape of long stripes, a regulating gate is set. An outlet of the rice field is communicated with the second water reservoir and which is communicated with the water inlet opening of the rice field via the reflux pump.

The invention relates to the field of slow/controlled release fertilizer, in particular to a urea-formaldehyde-based multi-nutrient slow/controlled release fertilizer and a preparation method thereof. The urea-formaldehyde-based multi-nutrient slow/controlled release fertilizer comprises ammonium polyphosphate, inorganic silica gel and urea-formaldehyde, wherein the phosphorus-oxygen double bond of ammonium polyphosphate can at least form hydrogen bond linkage with a urea-formaldehyde molecule chain, the hydroxyl group of the inorganic silica gel can at least form hydrogen bond linkage with the urea-formaldehyde molecular chain, and ammonium polyphosphate, inorganic silica gel and urea-formaldehyde together form a hydrogen bond associated polymer network structure. The invention can prepare a urea-formaldehyde-based multi-nutrient slow/controlled release fertilizer comprising a strong hydrogen bond network structure by using a conventional aqueous solution polymerization in combination with a normal temperature extrusion granulation process, avoiding the coating process in the latter stage of the preparation of a coated fertilizer, achieving a simple and effective preparation process, and saving a lot of manpower and material resources. The urea-formaldehyde-based multi-nutrient slow/controlled release fertilizer provided by the invention can stably and continuously release nitrogen nutrient throughout the release period, thereby making up for the shortcoming of excessively long nutrient release period of the existing urea-formaldehyde fertilizers.

A method for breeding a new variety of a ratoon rice crop and a cultivation method for the new variety of a ratoon rice crop. The method comprises: breeding a photosensitive variety of a rice crop; growing a ratoon rice crop under conditions of a long photoperiod; and taking corresponding cultivation measures to extend the growth duration of the ratoon rice crop. The invention increases grain yield while also permitting more uniform maturity of a ratoon rice crop. When compared to existing methods for cultivating ratoon rice crops, the invention greatly improves the grain yield and quality of a ratoon rice crop, and has economic and social benefits.

A method for breeding a new variety of a ratoon rice crop and a cultivation method for the new variety of a ratoon rice crop. The method comprises: breeding a photosensitive variety of a rice crop; growing a ratoon rice crop under conditions of a long photoperiod; and taking corresponding cultivation measures to extend the growth duration of the ratoon rice crop. The invention increases grain yield while also permitting more uniform maturity of a ratoon rice crop. When compared to existing methods for cultivating ratoon rice crops, the invention greatly improves the grain yield and quality of a ratoon rice crop, and has economic and social benefits.

The present invention discloses a CIELAB color space-based quantitative testing and analysis method for rice seed viability, and the method comprises removing husks on surfaces of rice seeds, soaking and imbibing the rice seeds without the husks removed, staining the rice seeds by using a TTC staining solution, and longitudinally cutting the rice seeds along embryos; converting the longitudinal section image of the rice seed from an RGB color space to a CIELAB color space, and calculating L value, a value and b value per unit area of the rice embryo as a staining intensity per unit area, and converting the staining intensity into a rice seed viability score according to a pre-established conversion model of the staining intensity and the rice seed viability score. According to the present invention, a reference result can be provided for the rapid, accurate and objective evaluation of the seed viability.

The present invention provides a method for rice cultivation via drip irrigation under a plastic film, comprising seed preparation, land preparation, sowing, seedling management, irrigation management, fertilization management, pest control and other steps, wherein seeding density of the sowing is 33300-36000 holes/mu, preferably 33300 holes/mu, or the seeding density is 30500-32600 holes/mu, preferably 30500 holes/mu. Previously, the conventional film with width of 105 cm or 145 cm is adopted for cotton culture stage in Xinjiang, but these films have following disadvantages: lower land utilization rate, resulting in relatively low seeding density, and difficulty in the process of adjusting row spacing and increasing seeding density, lower ground coverage rate, larger area of open ground, causing more weed relatively. Therefore, using wide film cultivation obtains relatively high yield if other planting conditions are the same.

The present invention provides a method for rice cultivation via drip irrigation under a plastic film, comprising seed preparation, land preparation, sowing, seedling management, irrigation management, fertilization management, pest control and other steps, wherein seeding density of the sowing is 33300-36000 holes/mu, preferably 33300 holes/mu, or the seeding density is 30500-32600 holes/mu, preferably 30500 holes/mu. Previously, the conventional film with width of 105 cm or 145 cm is adopted for cotton culture stage in Xinjiang, but these films have following disadvantages: lower land utilization rate, resulting in relatively low seeding density, and difficulty in the process of adjusting row spacing and increasing seeding density, lower ground coverage rate, larger area of open ground, causing more weed relatively. Therefore, using wide film cultivation obtains relatively high yield if other planting conditions are the same.

The invention relates to a method for producing for producing soluble potassium sulfate by recrystallization of crude potassium sulfate wherein the crude potassium sulfate contains an amount of potassium, calculated as K.sub.2O of about 15 wt % or higher preferably about 40 wt % or higher and has either more than about 0.07 wt % insoluble material, and/or a dissolution speed wherein at 3 min dissolution of 100 gram product in 1 L cold water (20 C.), without stirring the amount of dissolved potassium sulfate of less than about 90% and/or a pH of about 6 or higher as a 1% dissolved crude potassium sulfate, wherein the method comprises the following steps: crude potassium sulfate is dissolved, the dissolved potassium sulfate is subjected to a solid material removal step, potassium sulfate is crystallized, while optionally an acid is provided before, during or after the crystallization step of the potassium sulfate and whereafter the obtained potassium sulfate is separated and dried, wherein the particle size of the crystalline material is controlled to be within the ranges provided, optionally with sieving and/or grinding, preferably by sieving, such that the resulting potassium sulfate crystalline material conforms with the following characteristics: the amount of insoluble material is less than about 0.05 wt %, a 1 wt % solution of the potassium sulfate has a pH below about 6, and/or 1 pH unit lower than the pH of the crude potassium sulfate, the fraction obtained after crystallization has an average particle size within the following parameters: (i) d90<about 0.6 mm, (ii) d10>about 0.02 mm, and (iii) dust amounts to about 0.4 wt % or less, whereby the potassium sulfate contains more than 51% potassium, calculated as K.sub.2O.