湖南再生稻品种筛选研究

水稻的再生特性 ,是各类水稻品种的“共性” ,但各个品种的再生程度和条件有所不同 ,再生稻的更快更好发展 ,要有优良的再生稻品种基础。为了在湖南寻找再生能力强、两季产量高而稳的再生稻品种 ,我所在２００１年从全省各地引进２５个目前正在推广及利用的中晚稻新品种、新杂交稻组合进行品比筛选试验及小面积示范。部分品种 (组合 )作一季稻———再生稻栽培表现突出。现将试验结果初报如下 :一、试验概况１.供试品种 (组合 )供试常规稻品种共１０个 :湘中籼２号、湘中籼３号、湘中籼４号、湘晚籼５号、湘晚籼６号、湘晚籼９号、湘晚籼１…     

湖南省木薯产业发展研究

分析湖南省木薯产业的发展现状,发展木薯的可行性及湖南省木薯发展存在的问题,提出湖南省木薯产业的发展策略,为湖南省木薯产业发展提供决策参考。     

湖南省单季稻品种筛选研究

通过对10个杂交稻的试验表明,Ⅱ优86、Ⅱ优084、准两优527和D优7号等4个组合综合农艺性状较好,产量较高,适宜在湖南省作单季稻种植。     

Partition of geogenic nickel in paddy soils derived from serpentinites

Serpentinitic soils contain high concentrations of geogenic Ni. During serpentinitic mineral weathering, the Ni released from soils into ecosystems could be a source of non-anthropogenic metal contamination. In this study, soil samples were collected from two pedons in paddy fields in Taiwan and Japan; these samples were used to explore the profile distribution of total and labile Ni, demonstrating the contribution of Ni-bearing Fe and Mn oxides to the Ni partition in these soils. Serpentine and chlorite were the dominant primary minerals; thus, the soils reflected serpentinitic characteristics and exhibited high background concentrations of Ni. The total Ni content ranged from 240 to 520 mg kg^?1. Repeated redox and leaching cycles caused the redistribution of Ni in the paddy soils. The diethylenetriamine pentaacetate (DTPA)-extractable Ni, an availability index of Ni, increased as the soil depth decreased in the two pedons. An additional pool of labile Ni was present in the soils because the Ni concentration determined using a 0.1 N HCl extraction was much higher than was that determined using the DTPA extraction. Fe and Mn oxides were closely related to the labile Ni in these paddy soils. However, Ni was predominantly retained by amorphous and crystalline Fe oxides rather than Mn oxides. Shortening the flooded duration of paddy field is required to reduce the solubility of Ni because that the labile Ni and redox-sensitive Fe oxides can affect both the paddy soils and environment when Ni is released into the soil solution and becomes bioavailable under reducing conditions.     

The effect of waterlogging on electrochemical properties and soluble nutrients in paddy soils

This study was conducted to investigate the influence of waterlogging on availability of nutrients in paddy soils. The five soils were incubated under a waterlogged condition at 30 °C for 12 weeks. The EC, Eh, pH, NH₄, K, Na, Ca, Mg, Cl, P, Fe, and Mn of soil solutions were monitored over the waterlogged period. The Eh values generally dropped to the lowest point within 14 days of waterlogging, then increased, and reached equilibrium after 8 weeks of waterlogging. The soil pH decreased in the first 2–4 weeks of waterlogging. The EC values increased partly due to dissolution of soluble salts in the first 2 weeks. The concentrations of soluble NH₄ were significantly increased with waterlogging, reached maximum values at week 4–6, and then declined to the initial level. Waterlogging increased the concentration of soluble K, Ca, Mg, Fe, and Mn ions, the magnitudes of changes were greatly affected by soil properties. Increases in soluble Na, K, Ca, and Mg were attributed to the increase in solubility of insoluble salts and increase in competition for the exchange sites. Increases in soluble Fe and Mn induced by waterlogging were attributed to the dissolution of Fe and Mn oxides under reduced conditions.     

湖南优质稻品种品质指标间的相关性分析

对湖南省评选出的221个优质稻品种(组合)的主要米质指标进行了分析,探析了品质性状与评定等级的关系。结果表明,在一定范围内,稻米垩白粒率和垩白度越大,等级越低;而粒型长宽比和胶稠度越大,等级越高。湖南省二、三等优质品种的出糙率要求高于国家相应标准,垩白度和胶稠度要求低于国家相应标准。30年来,湖南省评选的优质稻品种米质有较大改善,但垩白粒率、垩白度仍普遍偏高。相关回归分析表明,稻米垩白粒率与垩白度呈极显著正相关,垩白粒率、垩白度与出糙率、精米率呈显著正相关,与粒型长宽比、整精米率、胶稠度、碱消值和食味值呈极显著负相关;粒型长宽比、整精米率与胶稠度、碱消值和食味值呈极显著正相关。     

湖南稻田耕作制度改革的形势与对策

总结了湖南从1999年以来实施稻田耕作制度改革所取得的主要成效，阐明了这一轮稻田耕作制度改革的新特点，分析了存在的主要问题．并有针对性地提出了稳步推进我省稻田耕作制度改革的对策措施。     

湖南省主要黄花菜品种生长发育和养分吸收规律研究

于2004年3～8月,在长沙对2001年冬季从湖南黄花菜主产区祁东和邵东两地引进的7个黄花菜品种分别进行定株观察,研究其移栽后的生长发育和养分吸收规律。结果表明,7个黄花菜品种叶片数、株高和苗数相差较大,但在整个生育期间出叶速度、株高变化幅度和苗数变化基本保持一致。不同品种总生物产量和花蕾产量相差悬殊,二者均以猛子花最高,茄子花最低。不同发育阶段相比,均以花蕾期生物产量最高,占全生育期生物产量的50％左右,苗期和抽薹期的生物产量相差不大,各占全生育期生物产量的20％～30％。黄花菜全生育期的N,P,K吸收量大小顺序为K〉N〉P,其中花蕾期的养分吸收量占全生育期的50％～80％,苗期和抽薹期吸收量差不多。花蕾期茎叶吸收P,K量明显高于苗期和抽薹期的吸收量,吸收N量则差不多。     

湖南省晚稻品种演变分析

对1981-2000年20a来湖南省晚稻品种(含杂交稻组合，下同)的演变进行了分析。湖南省晚稻品种的演变呈现出如下持点：杂交稻占主导地位，且比例不断扩大；威优系统和汕优系统构成杂交稻主体；常规稻主栽品种逐步实现优质化；品种数目不断增多，单个品种播种面积减少；超过68％的品种年播种面积低于6700hm^2。对产生这些现象的原因进行了探讨。     

论湖南黑茶产业在新世纪的发展

湖南发展黑茶优势明显：一是黑茶乃促进民族团结的桥梁与纽带;二是黑茶既有牢固的传统市场,又有广阔的潜在市场;三是黑茶采制适于全程机械化,有利于产业化经营;四是黑茶耐贮藏,并具特殊陈香品质;五是各级政府高度重视。主要不足之处是茶园基础薄弱,加工条件差,产品质量不一,品牌建设亟待加强。几点建议：（一）大力推广良种,夯实茶园基础;（二）切实改造茶厂,确保黑茶品质;（三）研发多元产品,开拓两个市场;（四）弘扬黑茶文化,扩大社会影响;（五）加强品牌建设,改革产销体制。     

Pedo-transfer function for saturated hydraulic conductivity of lowland paddy soils

In paddy field, soil saturated hydraulic conductivity (K _s) plays as an important component in the calculation of irrigation requirement of the water balance equation and also for irrigation efficiency. Several laboratory and field methods can be used to determine K _s. Laboratory and field determinations are usually time consuming, expensive and labour intensive. Pedo-transfer functions (PTF) serve to translate the basic information found in the soil survey into a form useful for broader applications through empirical regression of functional relationships, such as simulation modelling. Since PTFs have not been applied to paddy soils in the study area, a lot of field measurements will require high labour input to determine K _s hence high cost. This study attempts to seek a simplified method for determining K _s values based on common existing soil properties through PTF technique. Soil samples (n = 408 samples) were collected randomly depending on the soil series within the 2,300 ha Sawah Sempadan rice cultivation area. Both field work and laboratory work were carried out. The samples were then analysed for the following properties: dry bulk density (D _b), soil particle percentage (Sand-S, Silt-Si and Clay-C), organic matter (OM) and geometric mean diameter (GMD). The measured K _s values were obtained by using the falling head method. The parameters were then used as inputs for developing a K _s model by regression analysis using Statistical Analysis System (SAS) package. Stepwise regression analysis was applied to determine the best fit model based on R ² and significant level. The results of the study showed that there is a high spatial variability of the saturated hydraulic conductivity in the paddy area. The best regression model for estimating K _s was based on C, D _b, OM and GMD with the dependent variable (K _s) in a form of natural logarithm. The model inputs introduced by stepwise regression are commonly available therefore, this model is useful to replace the conventional method.     

Dynamics of cadmium concentration in contaminated rice paddy soils with submerging time

This study examined the change in the speciation of cadmium (Cd) in contaminated rice paddy soils with prolonged submergence. Three Changhua soils (CH1, CH2, and CH3) from central Taiwan and three Taoyuan red soils (TY1, TY2, and TY3) from northern Taiwan with different levels of heavy metal contamination were selected for the study. The Cd, Fe, Mn, soil pH, and Eh in soil solutions were determined as a function of submerging time. During submergence, the Fe and Mn concentration increased, while the SO₄ ^2? concentration decreased. The concentrations of Cd immediately increased in the soil solutions after a short submerging time and then decreased with further submergence. The sequential extraction showed that the exchangeable fraction decreased and the oxide-bound fraction increased after submergence. According to preliminary calculations of the MinteqA2 program, sulfate cannot be reduced to sulfite or sulfide under the soil Eh and pH values observed for the soils after prolonged submergence. Thus, the observed decreases of sulfate concentration may result from sulfate reduction in the micro-environments, which cannot be accounted for by the thermodynamic calculation. The reduction of sulfate to sulfide may subsequently result in the formation of CdS precipitate, which attributes to the decreases of Cd concentrations in the soil solutions after prolonged submergence.     

Impacts of perforated sheet pipe installation on some paddy soil properties

Paddy and Water Environment - Today, the world’s vision emphasizes the development of climate-adaptive agriculture for food security and provision of water with safe technology. Under extreme...     

湖南桂阳烟区云烟87最适移栽期初探

2012年在湖南郴州桂阳县对烤烟品种云烟87的适宜移栽期进行了试验研究。结果表明：在当地耕作制度和栽培水平下,云烟87最适宜的移栽期为3月15日至3月25日,此时移栽有利于特色优质烟叶的形成和烟叶风格的彰显。     

Chemical fractionation of seven heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, and Zn) in selected paddy soils of Iran

The content and fractionation of seven heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, and Zn) were determined in 28 surface soil samples (0–20 cm) of agricultural topsoil from Isfahan Province in central Iran. The order of abundance of metals in the soils was Fe (1240.4 mg kg^?1) > Mn (95.7 mg kg^?1) > Pb (51.6 mg kg^?1) > Zn (23.8 mg kg^?1) > Ni (13.4 mg kg^?1) > Cu (7.0 mg kg^?1) > Cd (2.8 mg kg^?1). Iron, Mn, Ni, Pb, and Zn existed in paddy soils mainly in Fe-Mn oxides (53.6 %, 65.2 %, 40.4 %, 40.8 %, 53.3 %, respectively), whereas Cu and Cd occurred essentially as residual mineral phase (41.4 %) and carbonate (36.1 %), respectively. The mobile and bioavailable fractions of Cd, Cu, Fe, Mn, Ni, Pb, and Zn in paddy soils averaged 48.8, 20.8, 0.79, 29.2, 28.5, 41.1, and 24.8 %, respectively, which suggests that the mobility and bioavailability of the seven metals probably decline in the following order: Cd > Pb > Mn ≥ Ni > Zn > Cu ? Fe, suggesting greater contribution of anthropogenic Cd. As Cd in soil is easily accumulated by plants through the root system, the concentration of Cd in these paddy soils could be a concern to human health.     

湖南亚麻生产及其产业化问题的探讨

本文根据近年来湖南亚麻引种栽培和祁阳县亚麻生产及初加工的实践 ,对湖南亚麻生产及其产业化的意义、优势和市场前景等问题进行了详细论述 ,分析了湖南亚麻生产及其产业化开发过程中存在的问题和具体的解决途径。     

湖南休闲农业的产业特征分析

在湖南省休闲农业经营主体面上调查、县级农业行政部门摸底调查和实地考察的基础上,得到了全面洋实的数据资料,在此基础上分析了湖南休闲农业产业的总体特征、休闲农业经营主体的地域分布特征和湖南休闲农业产业的主要经济指标,为湖南休闲农业领域提供了丰富的基础数据,并形成了湖南休闲农业的分类学结论和经济学特征指标。     

湖南常德地区棉花黄萎病菌培养特性及致病力分化研究

从常德4个主产棉县采集棉花黄萎病株,分离获得37个黄萎病菌单孢菌株,对其培养特性和致病性进行了研究。菌株培养性状研究表明,在分离的37个菌系中,菌丝型菌株最多,其次是中间型,最少的是菌核型,3种类型菌株分别占所有菌株的67.6%,24.3%和8.1%。选用陆地棉感病品种冀棉11号作为鉴别寄主对供试菌株做致病力测定,结果表明,37个菌株可归为3个类群:I型、Ⅱ型和Ⅲ型,分别占供试菌株的13.5%,8.1%,78.4%,证实常德植棉区黄萎病菌种群存在明显的致病力分化。