杨梅的需钾特性及施钾对杨梅的增产效应

钾对杨梅产量和品质的影响仅次于微量元素硼。杨梅对N：P2O5：K2O的需要比例分别为1：0．5：2．69。浙江省杨梅主产区土壤（0-20cm）的全钾和速效钾含量分别为1．81-2．41g／kg和83-121mg/kg。施钾能显著提高杨梅产量和改善果实品质。株产50kg果实的杨梅树以施用1．0～1．5kg氯化钾并配施50g硼砂的效果较好，杨梅进行叶面施钾时以喷施0．5％KCl或0．5％磷酸二氢钾的效果较佳。     

Effects of Application of Boron on Growth,Yields, and Quality of Red Bayberry

ABSTRACT

Three field experiments at three sites in east Zhejiang Province were conducted to determine the influence of applications of boron (B) on growth, yield, and quality of the red bayberry trees (Myrica rubra Sieb. et Zuca) with a manure species of “Buqizhong” in Linhai city. Ground B application or foliar B spraying significantly improved length and incidence rates of spring and summer shoots and increased fruit set rates, which resulted in the increases in fruit yield (13.7–17.5% for ground B application or 13.2–27.3% for foliar B spraying) and in improvement of fruit quality. The optimum yields were recorded with the treatments of ground B application of 40 g tree^?1 of borax or foliar B spraying of 2.0 g L^?1 of borax. Spring shoot incidents for the treatment of ground application of 50 g borax tree^?1 every year during the experiment (4B₅₀) were significantly higher than that for the treatment of ground application of 50 g borax tree^?1 only in the first year of the experiment (B₅₀), but the yield difference between them was not significant at P = 0.05. The increased yield effect of ground B application could last for 3 years. Boron application of red bayberry trees can be carried out by foliar-spraying 2.0 g borax L^?1 every year or ground application of 50 g borax tree^?1 every 3 years. The results of this study showed that application B could significantly improve the growth and increased fruit yield and quality of the red bayberry trees not exhibiting any vegetative symptoms of B deficiency.     

Effects of Boron and Paclobutrazol on Growth,Fruit Set,Nutrient Uptake,and Alternate Bearing of Muye Red Bayberry

Alternate bearing, resulting mainly from boron (B) deficiency, and excessive fruits in the alternate years of red bayberry trees are the most important limiting factors for production. This investigation was conducted on 18-year-old Muye red bayberry trees (Myrica rubra Sieb. et Zuca) in a commercial red bayberry orchard located in Laxi County, Zhejiang Province in 2006–2007.The results indicated that foliar application of paclobutrazol (PB) significantly increased the vegetative growth parameters (i.e., spring shoot incident and spring shoot length). Spring shoot incidents and spring shoot lengths of red bayberry were increased with increasing PB concentrations, but the optimum fruit yield and quality were obtained from foliar-applied PB at 100–200 mg L^?1 at full bloom. Foliar application of PB increased the contents of N and K in the leaves with increases of PB concentrations up to 300–600 mg L^?1. Fruit quality of red bayberry trees treated with PB or and boron fertilizer (BF) was improved at full bloom. Foliar application of PB reduced the percentage of fruit set by 62.1% in the year after treatment with PB but increased the yield by 49.0% the following year. Foliar application of PB at 100–300 mg L^?1 gave the most significant improvement in fruit quality: increase in fruit weight, soluble solid content, and the ratio of soluble solids (SS)?/?total acidity (TA) and decrease in total acidity. Foliar application of BF slightly reduced the fruit yields in the current year but significantly increased those the following year. Combined application of BF and PB or application of PB alone markedly reduced the fruit yields in 2006 by 40.5% and 43.8%, respectively, but markedly increased those by 44.6% and 17.8% in 2007, respectively. The effects of alleviating alternate bearing of red bayberry for different treatments followed the order of combined application of FB + PB > PB > BF > control. It is suggested that PB and BF can be used to alleviate alternate bearing.     

垂吊型矮牵牛叶片培养不定芽发生和微繁研究

以垂吊型矮牵牛叶片为材料 ,建立了垂吊型矮牵牛叶片高效不定芽发生、植株再生和微繁的技术体系。研究了不同激素及其组合对叶片不定芽发生、壮苗和生根的效应。结果显示 ,MS +BA 2mg L +NAA 0 1mg L是叶片不定芽发生的适宜培养基 ;MS +BA 0 5mg L +IBA0 1mg L +GA 0 5mg L是不定芽形成壮苗的适宜培养基 ;MS +IAA 0 1mg L是壮苗生根的适宜培养基 ;草炭珍珠岩基质是生根苗移栽的适宜基质     

NORMS FOR MULTIVARIATE DIAGNOSIS OF NUTRIENT IMBALANCE IN THE EAST AFRICAN HIGHLAND BANANAS (MUSA SPP. AAA)

Despite low yields and soil fertility problems, fertilizer use in the East African Highland banana (AAA-EA) production is absent. High fertilizer costs increase the need for site-specific fertilizer recommendations that address deficiencies. This study aimed to derive and compare norms for AAA-EA bananas, using Compositional Nutrient Diagnosis (CND), Diagnosis and Recommendation Integrated System (DRIS), and a DRIS that includes a filling value (DRIS-R_d), and study nutrient interactions. Data on foliar nitrogen, phosphorus, potassium, calcium, and magnesium concentrations, and plant performance were obtained from 300 plots in Uganda. CND indices were closely related to DRIS and DRIS-Rd indices (R² > 0.965). Four nutrient interactions were common in both low and high bunch weight subpopulations. Although the three approaches can be used to determine nutrient imbalances in AAA-EA bananas, we recommend CND for ease of use. Diagnosis of nutrient deficiencies should be based on methods that identify plant nutritional imbalances.     

冬枣秋季不同枝条叶施15N-尿素的贮藏、分配及再利用

大田条件下,以6年生冬枣为试材,研究冬枣晚秋不同枝条叶施15N-尿素后,休眠期15N的贮藏、分配及翌年盛花期15N的再分配和利用。结果表明:晚秋叶施15N-尿素,休眠期树体枝干和根系中可检测到15N;翌年盛花期时,处理枝新生器官(枣吊、叶片、花)中可检测到15N。休眠期15N主要贮藏于地上部多年生器官,包括处理枝条和附近多年生器官。与休眠期相比,翌年盛花期时处理枝条的Ndff%显著下降,新生营养枝和多年生枝分别下降了59.13%和69.05%。贮藏15N再分配到新生器官,主要用于叶片和枣吊的生长,分配势随新生器官生理年龄的增加而增大(枣吊>叶片>花)。与新生营养枝处理不同,多年生枝处理的地上部枝干中贮藏15N向新生器官及枝干运输同时向下分配运输用于根系生长。