应用多元回归原理预测初产母牛产奶量的研究

通过黑龙江省香坊实验农场奶牛场50头初产牛90天、120天估测305天产奶量的回归方程：y＝851．93－1．485X1＋3．115X2，经检验准确度（R）可达88．57％．在生产实践中，利用此方程可以90天和120天的产奶记录，提前选择对奶牛育种工作起重点作用的初产母牛．

Distribution of Rapeseed Clubroot Disease in Hubei Province and Evaluation of Yield Loss

[Objective] The aim of this study was to reveal the distribution of rapeseed clubfoot disease in Hubei Province and to assess the yield loss caused by the pathogen, Plasmodiophora brassicae. [Method] Field surveys were conducted in Shayang, Dangyang, Zhijiang, Yidu and Changyang of Hubei Province during 2009- 2011. Clubfoot disease of rapeseed samples from the surveyed locations were con- firmed by PCR detection and plants infection experiment. The factors of yield and plot yields influenced by clubroot disease were determined in plot experiment. [Re- salt] Rapeseed clubroots were confirmed in Zhijiang and Dangyang and not found in Shayang and Yidu. Clubroot was found in cruciferous vegetables but not in rapeseed d in Changyang. Infection of P. brassicae significantly decreased of the first effective branch numbers of rapeseed, effective pod number per plant, seed number per pod and 1 000-grain weight. Yield of infected rapeseed decreased by 56.4% over non-infected control. [Conclusion] Rapeseed clubroot disease mainly distributed in Zhijiang and Dangyang of Hubei Province. The disease had an economic impact on rapeseed production.

Effects of Tiller-inhibitor on Growth and Yield Formation of Super Early Hybrid Rice Jinyou458

[Objective]The paper was to study the effect of tiller-inhibitor on the growth and yield formation of super early rice Jinyou 458.[Method] Two treatments including spraying tiller-inhibitor（TI） and spraying water（CK） at the SN-n stage were set in the test,the effect of tiller-inhibitor on yield and its components,leaf and plant morphology,field microclimate at booting stage and quality characteristics of rice population were studied.[Result] Spraying tiller-inhibitor could effectively reduce the occurrence of invalid and inefficient tillers,increase the proportion of high effective tillers（tiller with 4 or more leaves） in tiller composition at the maximal tiller stage.The panicle length,spikelets per panicle,spikelets density,number of secondary branches and the secondary spikelets,seed setting rate of rice plant sprayed with tiller-inhibitor were significantly higher than CK.Meanwhile,spraying tiller-inhibitor could increase plant height,biomass weight and leaf area index of rice population during middle and late stages of rice growing,improve the leaf temperature of top three leaves and the light transmittance of rice population at the booting stage,increase the leaf SPAD value,thus enhance photosynthetic capacity of rice plants.It also showed the characteristics of elongating the internode of rice plant and decreasing the stem thickness,etc.[Conclusion] The panicle-bearing rate of stems and tillers,effective panicles,spikelets per panicle,seed setting rate and 1 000-grain weight had coordinately increased after spraying tiller-inhibitor,thus increased the yield.

Effect of Fulvic Acid on Growth and Yield Components of Direct Seeding Rice

ObjectiveThis study aimed to investigate the effect of fulvic acid on the growth and yield components of direct seeding rice （Nanjing 44）. MethodThe rice seeds were soaked in 0 （water as a control）, 1, 2, 4 and 6 g/L fulvic acid （FA） before sowed. Then, the rice morphological indices, leaf chlorophyll content, photosynthesis parameters, root activity and chlorophyll fluorescence parameters were measured in the following field studies. ResultCompared with the control, the leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance and dry matter weight and some fluorescence parameters such as the maximum photochemical efficiency of photosystem II （PSII） （Fv/Fm）, excitation energy capture efficiency of opened PSII reaction center （Fv’/Fm’） and efficiency of the open reaction centre （ΦPS II） increased by different levels at both jointing stage and heading stage of direct seeding rice, whose seeds were soaked by FA with different concentrations. High FA concentration （4-6 g/L） significantly increased the cultivated rice leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance, transpiration rate and dry matter weight by 10.32% -22.88% , 5.88% -13.11% , 12.16% -26.84% , 11.43% -88.46% , 10.63% -21.63% , 18.49% -19.68% , respectively, thereby improving the physiological function and light energy transform efficiency of rice at the growth stage. With FA concentration increasing, the yield, effective panicles, grain number per panicle and seed setting rate were increased significantly compared with the control by 17.52%-18.71%, 3.46%-3.85%, 6.30%- 6.51% and 7.82%-8.69% respectively. ConclusionSoaking rice seed with FA could be considered as an effective way to improve the rice competitiveness at early growth stage.

Effect of Controlled Release Nitrogen on Wheat Growth and Yield

[Objective] Effects of controlled release N fertilizers on wheat growth and yield were studied to provide reference for the application of controlled release fertilizers on wheat. [Method] A field experiment was conducted to study the effects of different types and levels of controlled release N fertilizers on the growth and yield of wheat. In this experiment, a treatment with the application of common urea and potassium chloride（common fertilizer） was established, and treatments with controlled release N fertilizers A and B with different coating materials were also established. [Result] The results showed that under the condition of the same P and K levels, controlled release N fertilizer A at a proportion of 100%, controlled release N fertilizer A at a proportion of 80% and controlled release N fertilizer B at a proportion of 80% could promote wheat growth, optimize yield components, and increase the amount of dry matter accumulation and grain yield. [Conclusion] One-time application of controlled release N fertilizer could be adopted in wheat production to achieve the purposes of saving fertilizer, saving labor and increasing efficiency.

Effects of Plastic Film Mulching on Physical Characters of Soil and Yield and Yield Components of Sweet Potato

Field experiments were carried out to study the effects of plastic film mulching on soil physical characters, including soil temperature, soil moisture content and soil bulk density, and yield and yield components of sweet potato. The results showed that plastic filming mulching increased soil temperature. Considering the soil temperature-increasing effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. However, with the deepening of soil layer, the warming effect of plastic film mulching was weakened. Black or white plastic film mulching was conducive to low T/R value, especially in the early growth stage of sweet potato. Plastic film mulching significantly improved the storage root yield of sweet potato. In terms of yield-improving effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. The storage root num- ber per plant showed a downward trend, but the weight of single storage root was increased.

Study on Developmental Durations and Fecundity of Phenacoccus solenopsis Tinsley on Four Species of Hosts

[Objective] The aim was to study on the effect of hosts on development and reproduction of mealybug （Phenacoccus solenopsis Tinsley）. [Method] Observation was conducted on developmental durations and fecundity of Phenacoccus solenopsis Tinsley fed on Gossypium spp., Nicotiana tabacum, Solanum tuberosum L and Hibiscus rosa-sinensis. [Result] There were differences among all durations, generation durations and fecundities of the mealybug adult females. Specifically, the generation durations on cotton （Gossypium spp.）, tobacco（ Nicotiana tabacum）, potato （Solanum tuberosum L） and Hibiscus rosa-sinensis were 30.2, 28.2, 37.3, and 27.7 d, and the fecundities per female were 626.0, 417.2, 552.5, and 183.2 ind., respectively. [Conclusion] The mealybug would have strong pontential in population growth when fed on cotton, tobacco and potato.

Characteristics of Retoon Rice Yield Components and Relationship of the Characteristics with Rate of Bud Emergence and Root Activity

[Objective] The aim was to study on characteristics of retoon rice yield components, and relationship of the characteristics with born bud rate and root ac- tivity of retoon rice before harvesting. [Method] Eighteen mid-season hybrid rice va- rieties approved recently were taken as materials in high-yield cultivation conditions. Characteristics of retoon rice yield components were analyzed, and relationship of yield components characteristics with the rate of bud emergence and root activity of retoon rice before harvesting was explored, based on related data. [Result] Highly- yielding retoon rice is characterized by high effective ear number （Xl） and high set- ting percentage （X4）; the number of germinated shoots the 5^＊ d after first-batch rice was cut is a key factor for retoon rice yield and was of positive correlation with re- toon rice seedlings and effective ears, with correlation coefficients at 0.80^＊＊ and 0.76^＊＊. In addition, bleeding sap was of positive correlation with grain number and setting percentage of retoon rice and correlation coefficients were 0.50^＊ and 0.48^＊＊, and of positive correlation with average panicle weight, with correlation coefficient at 0.63. [Conclusion] It is an effective way for the rate of bud emergence and root activity at lar ecological zones. mproving retoon rice yield to increase harvesting in the test sites and simi lar ecological zones.

Effects of Nitrogen Application Amount on Growth Characteristics,Boll Development and Lint Yield of High Quality Cotton

[Objective] This study aimed to explore an optimum application amount of nitrogen for cotton cultivation. [Method] In this study, a field experiment was conducted to investigate the effects of nitrogen application amount on the growth characteristics, boll development and lint yield of high quality cotton line FZ-1. [Result] Compared with the nitrogen level of 225 kg/hm2, the lint yield had increased by 28.46% and 18.73%, respectively, with the nitrogen application amount of 300 and 375 kg/hm2. When the nitrogen application amount had increased from 225 to 300 kg/hm2, boll number per plant, boll weight and lint yield had significantly increased. At the nitrogen level of 375 kg/hm2, however, the effects of increasing lint yield were significantly less than that at the nitrogen level of 300 kg/hm2. Compared with the nitrogen levels of 225 and 375, 300 kg/hm2 of nitrogen was the optimum application amount to improve the plant height, daily increment of plant height, number of fruit branches, number ratio of nodes to fruit branches, boll volume and seed cotton weight per boll. [Conclusion] The rational management of nitrogen is the most effective way to promote the growth and development of cotton plants, ensure high yielding ability and minimize the environmental pollution caused by the overuse of nitrogen. This study had provided a sound nitrogen application strategy for the cultivation of this high-quality cotton line in the field plantation.

Effect of Microbial Inoculum Fertilizer on the Growth and Yield of Super Hybrid Rice

The research designed four application quantities of 0, 2 250, 4 500 and 6 750 g/hm2 based on Liangyou No. 959 to explore the effects of microbial inocu- lure fertilizer on growth and yield of super hybrid rice. The results indicate that the treatment with traditional fertilizers and 4 500 g/hm2 HYT microbial inoculum fertilizer performed the best, where average number of tiller was 2.4 more than that of the control; the number of effective ear was 11.05% higher; yield increased by 10.3%. These have demonstrated that microbial inoculum fertilizer is of great value in pro- motion on super hybrid rice production.

Application Effects of Ultra-fine Powder Shaped Maize Seed Coating Agent in Spring Sowing areas in northeast China

The research explored adaptability maize seed coating agent in spring sowing and effects of ultra-fine powder shaped areas in northeast China. The results showed that germination potential and rate both improved around 5% and the num- ber of root increased by 4% in the treatments with ultra-fine powder shaped maize seed coating agent compared with the control group without seed coating. What＇s more, the treatments with ultra-fine powder shaped maize seed coating agent took advantages in terms of fresh weight of seeding, stem diameter, and dry weight. It is notable that control effects on underground insects performed the best, with per- centage over 94%, which is more excellent relative to other agents in markets. Therefore, ultra-fine powder shaped maize seed coating agent can be widely applied in spring sowing areas in northeast China, without side effects.

Effects of Different Application Times of Tillering Fertilizer on Grain Yield and Population Development of Double-cropping Rice Transplanted by Machine

The application of tillering fertilizer plays an important role in promoting rice tillering and improving rice yield. However, under the condition of mechanical transplanting, the optimal application time of tillering fertilizer is still unclear. In this study, the early rice cultivar Zhongjiazao 17 and late rice cultivar H You 518 were used as materials, and the effects of different application times of tillering fertilizer on yield and population development of double-cropping rice transplanted by machine were investigated. The tillering fertilizer was applied 7（D07）, 10（D10） and 13（D13） d after the transplanting, respectively. The results showed that compared with those in the D07 treatment groups, the yield of early rice in the D10 and D13 treatment groups were reduced by 9.4% and 3.8%, respectively, and the yield of late rice in the D10 and D13 treatment groups were reduced by 4.5% and 12.6%,respectively. However, there were no significant differences in rice yield among the treatment groups. The application time of tillering fertilizer showed significant effects on grain number per panicle and seed setting rate of early rice. The grain number per panicle in the D10 treatment group was significantly lower than that in the D07 treatment group, and the seed setting rate of the D13 treatment group was significantly lower than that in the D07 treatment group（P〈0.05）. For the late rice, the effect of application time of tillering fertilizer on effective tiller number was most obvious, and the effective tiller number in the D13 treatment group was significantly lower than that in the D07 treatment group（P〈0.05）. Compared with those in the D07 treatment group, the effective tiller numbers, leaf area indexes and biomasses in the D10 and D13 treatment groups were all trended to be decreased. Therefore,to improve the quality of population and fulfill the high-yielding potential of double-cropping rice transplanted by machine, the tillering fertilizer should be applied as early as possible after rice seedlings turn green.

Effects of Specific Gravity-based Seed Grading on Seed Germination, Seedling Emergence and Grain Yield of Hybrid Rice

Using the commercial seeds of two hybrid rice varieties including Lu- liangyou 996 and Liangyoupeijiu as the materials, four specific gravity-based seed grading treatments, Le., the specific gravity of 〈1.0 （T1）, 1.0-1.09 （T2）, 1.1-1.19（T3） and ≥1.2 （T4）, by selection with different saline solutions, and the control without seed grading （CK） were designed to study the effects of seed grading on seed germination, seedling emergence, seedling quality and grain yield. The results showed that the treatments of T2, T3 and T4 had higher or significantly higher seed germination rate, germination index and vigor index, seedling emergence rate and adult seedling rate than the CK, while T1 had significantly lower values of these traits than the CK. Compared with the CK, the number of spikelets per pani- cle was found to be the main reason for the yield increase of these treatments with high seed viability.

Effects of Combined Pollution of Pb and Cd on Growth and Yield of Rice

[Objective] The aim was to study the damage and the mechanism of combined pollution of Pb and Cd on rice growth,yield and quality of rice. [Method]Effects of combined pollution of Pb and Cd on the growth and yield of rice were studied by pot experiment with cultivating rice. [Result] Pb and Cd could promote rice growth at low concentration while inhibit plant height at high concentration; Pb and Cd stress reduced the number of rice tillers significantly,with the increasing of stress concentration,the decrease amplitude of the number of tillers was greater; the panicle per pot,seed setting rate,1 000-grain weight and yield of rice were reduced significantly by Pb and Cd stress,the grain number per panicle decreased significantly under low concentration of Pb and Cd but increased significantly under high concentration; the brown rice rate and milled rice rate increased significantly under low concentration of Pb and Cd while at high concentration of Pb and Cd,the both two reduced significantly,the head milled rice rate reduced significantly with the decreasing of concentration; The Pb and Cd content of grains were significantly positively related to the concentrations of Pb and Cd content in soil,it had excessively exceeded hygienic standard when the concentrations of Pb and Cd in soil were medium-high and the unqualified rate reached 333% and 122%. [Conclusion]The study had provided basis for the establishment of rice cultivation system in pollution areas.

Effects of FCMP Compound Fertilizer on Development and Yield of Early Rice

[Objective] The aim was to explore effects of FCMP compound fertilizer on growth, development and yield of early rice. [Method] Based on lower-graded phos- phate resource, effects of FCMP compound fertilizers on yield and growth of early rice in a field were researched. [Result] FCMP compound fertilizers 0, 1 and 2 en- hanced rice yield, increasing by 21.86%, 20.25% and 13.46%, compared with the rice applied with conventional fertilizer; number of productive ears and grain number per ear in unit area were improved by FCMP compound fertilizer, for example, the two factors achieved the highest with FCMP compound fertilizer 1, increasing by 11.70% and 19.63%. Furthermore, FCMP compound fertilizer promoted plant height and tiller number, maintained high photosynthetic efficiency, enhanced lodging-resis- tance and guaranteed stable and high yield. [Conclusion] The research is of theoret- ical and practical significance for further exploration of production techniques and application of FCMP compound fertilizer.

Effects of Biogas Fermentation Broth on Tomato Growth and Development

[Objective] This study aimed to examine the effects of biogas fermentation broth on tomato growth and development. [Method] The biogas fermentation broth of vegetable waste （cabbage leaves） was sprayed at different concentrations to tomato leaves throughout its growth period. Then, the quality indices of the tomato fruits were measured. [Result] Biogas fermentation broth increased the flowers, improved the contents of lycopene and vitamin C in tomato fruits. [Conclusion] The results provide a new direction for vegetable waste recycling.

THE GROUNDWATER RESOURCES AND ITSSUSTAINABLE DEVELOPMENTIN THE SOUTH EDGE OF TARIM BASIN

There is a potential to certain extend for groundwater development in the piedmont plain in south edge of Tarim Basin. If the surface water use keeps the scale as present, the maximum safe yield of groundwater is about 2.05 × 109m3/a that is 55.8% of the recharge. Thus the evapotranspiration discharge will reduce 60.4%, while spring water reducing 35.6%. If the surface water use rate is up to 80% and coefficient of canal water use increase to 0.55 in the future, the maximum safe yield of groundwater will reduce to 1.85 × 109m3/a with the recharge reducing to 3.1 × 109m3. However, the sustainable groundwater development is depended on the protection of the quality aspect linked with the quantity aspect. In particular, protection of the glaoier and water conservation forestry in the Kunlun Mountains and coordinating development of surface water and groundwater should be taken seriously. Besides, the legislation, administrative management and the technology construction, and ability construction are also critical important and necessary.

Digital Economy and High-Quality Industrial Development

In the 14th Five-Year Plan period(2021-2025),China has vowed to pursue high-quality industrial development.The digital economy drives high-quality industrial development by creating means of production,reducing transaction costs,transforming industrial organization,and improving the efficiency of resource allocation.The digital factor has become a key factor of production for high-quality development.Digital and user-created innovations are the new normal for cross-sectoral integration and innovation.Great progress has been made in China'high-quality industrial development driven by the digital economy.The rapid development of digital industries and industrial digitalization have reshaped the industrial division of labor and helped the ascension of related industries towards the medium-and high-end links of the global value chains.However,China still faces numerous challenges in the development of its digital economy;it lacks indigenous industrial innovation,depends on foreign supply of core technologies,and is ill-prepared for industrial digitalization.Much work remains to be done to further coordinate the development of some industries and foster digital ecosystems for the symbiosis of industrial chains.In furthering the high-quality industrial development driven by the digital economy,China should stay at the forefront of digital innovation,promote digital governance,enhance data factor agglomeration,and foster digital talents.

Advances in the Research and Development of Acrylic Acid Production from Biomass

The shortage of petroleum has resulted in worldwide efforts to produce chemicals from renewable resources. Among these attempts, the possibility of producing acrylic acid from biomass has caught the eye of many researchers. Converting the carbohydrates first to lactic acid by fermentation and then dehydrating lactic acid to acrylic acid is hitherto the most effective way for producing acrylic acid from biomass. While the lactic acid fer- mentation has been commercialized since longer times, the dehydration process of lactic acid is still under development because of its low yield. Further efforts should be made before this process became economically feasible. Because of the existence of acrylic acid pathways in some microorganisms, strain improvement and metabolic engineering provides also a possibilitv to produce acrylic acid directly from biomass by fermentation.

Current treatment of rectovaginal fistula in Crohn's disease

Rectovaginal fistula(RVF) continues to be the most difficult perianal manifestation of Crohn's disease to treat.This devastating and disabling complication has a significant impact on patients' quality of life and presents unique management challenges.Current therapeutic approaches include many medical therapeutics and surgical treatments with a wide range of success rates reported.However,current evidence is lacking to support any recommendation.The choice of repair depends on various patient and disease factors and basic surgical tenets.In this article,we review the current options to consider in the treatment of Crohn's-related RVF,and try to evaluate their effects on fistulae closure and quality of life.