土壤养分的空间分布及木薯产量障碍因子分析

采用地统计学的基本原理和方法,分析了广西武鸣县旱地土壤养分的空间分布状况及影响木薯产量的土壤障碍因子。结果表明,土壤的pH、有机质、速效P、速效K和有效Mo具有强烈的空间相关性,速效N、有效Cu和有效Fe具有中等的空间相关性,有效Zn和有效Mn具有弱空间相关性。运用GIS结合Kriging方法绘制的土壤养分障碍因子图,能够更加直观地了解到武鸣县旱地土壤养分的丰缺状况。在试验测试范围内,木薯产量与pH、有机质呈显著正相关,表明在酸性土壤中pH和有机质是影响木薯产量的促进因子;而土壤有效Fe含量较高,其含量与木薯产量呈极显著负相关,这可能是由于高含量有效Fe影响了其他养分的有效性,从而影响了木薯的产量。

施钾对木薯产量和品质及大中微量元素吸收的影响

【目的】研究不同施钾量对木薯产量、大中微量元素吸收及品质的影响,为木薯合理施钾提供理论依据。【方法】采用田间试验,以我国主栽木薯品种"SC205"为材料,K_2O施用量设0,60,120,180,240kg/hm2共5个水平,于收获期测定木薯薯块、茎秆、叶片的生物量及N、P、K、Ca、Mg、Mn、Cu、Zn含量,并测定薯块可溶性糖和淀粉含量。【结果】1)与不施钾相比,施钾可显著提高薯块、茎秆和叶片鲜产量,其中鲜薯增产9.87%~25.57%;随施钾量增加,鲜薯产量先增加后降低,K_2O施用量为60~120kg/hm2时,鲜薯产量较高。2)施钾可以明显提高薯块、茎秆和叶片的K含量,提高薯块的Mn、Zn、可溶性糖及淀粉含量,但Mg含量有所降低,同时还可以提高薯块、茎秆和叶片的K/N、K/P、K/Ca、K/Mg、K/Mn、K/Cu、K/Zn值。3)施钾能显著提高薯块K、Mn、Zn、可溶性糖、淀粉的积累量,其中可溶性糖和淀粉积累量的增幅分别为7.65%~32.91%和12.65%~53.41%,K_2O施用量为60~120kg/hm2时,薯块各矿质元素、可溶性糖及淀粉积累量均处于较高水平;施钾可显著降低钾素在薯块中的分配比例。4)薯块的P、K、Mn及可溶性糖含量与施钾量呈极显著或显著正相关。【结论】为获得较高的木薯产量、大中微量元素积累量、品质及经济效益,建议最佳的K2O施用量为95~130kg/hm^2。

灰色广义回归神经网络在木薯产量预测中的应用

将GM(1,1)预测模型与广义回归神经网络(GRNN)相融合,构建一种兼具两者优点、互补型的灰色广义回归神经网络(GGRNN)。以1985-2007年度广西木薯鲜薯总产量为数据样本,采用GGRNN模型进行广西木薯产量预测研究。研究结果表明,GGRNN训练期平均拟合指数、预测期平均拟合指数分别为0.99和0.93,分别比GM(1,1)模型高0.09和0.04。该组合模型在拟合精度和预测精度方面均优于单一的GM(1,1)预测模型,并具有自学习能力、非线性映射能力以及适应性强等优点,为木薯产量预测的定量化和智能化提供了一条有效途径。

中国木薯产量波动及影响因素分析

利用剩余法将木薯生产波动与长期趋势相分离,对中国48年来木薯生产变化趋势进行分析,计算中国木薯产量及木薯产量短期波动系数。结果表明:我国木薯生产波动幅度较大,整体上属于短期波动和古典波动,生产易出现大起大落的状况。

生物有机肥和化肥对木薯产量和淀粉含量的影响

研究于2013年以木薯品种"桂热4号"为材料,探讨了2种生物肥(木薯增产王和松土荣)和化肥对木薯产量和淀粉含量的影响。试验处理为:不施肥(CK),松土荣(M),NPK(化肥N:P2O5:K2O=100:50:100 kg/hm2),NPK+M(化肥+松土荣),75%NPK+M(75%化肥+松土荣),50%NPK+M(50%化肥+松土荣),T(木薯增产王),T+NPK(木薯增产王+化肥)。结果表明:施用松土荣和木薯增产王对木薯的鲜薯产量、淀粉含量、淀粉产量均无显著影响。其原因可能是厂家推荐施用量偏小。而化肥施用量处理显著,化肥施用量在推荐配方的75%及以上时才能显著增产。而且鲜薯产量随着化肥用量的上升而线性增加,说明了推荐配方的科学性。建议加大此2种生物有机肥的施用量。

施肥与盖膜微集雨集成技术对土壤性状及木薯产量的影响

【目的】探索木薯施肥与盖膜微集雨集成技术,为改善土壤质量、提高木薯产量提供科学依据。【方法】开展田间试验,处理1为施用木薯加工废弃物研制的生物有机肥＋测土配方肥＋盖膜微集雨技术（在行距畦面上利用农膜覆盖收集雨水进入木薯种植行沟的盖膜模式,盖膜行距畦面高于木薯种植行沟2-3 cm,行距畦面宽80 cm）,处理2为习惯施肥栽培（对照,不盖地膜）,每个处理施肥量以NPK总养分为900.0 kg/ha计。测定不同处理对木薯生长指标、产量及土壤理化性状的影响。【结果】处理1的土壤速效N、P、K,有机质、含水量、总孔隙度分别比处理2提高9.19%、9.17%、3.32%、8.25%、32.21%、9.60%,容重降低6.25%,可改善土壤p H。处理1木薯叶片叶绿素和叶片干物质、木薯杆茎径、木薯块根茎径、木薯块根长、单株块根条数、单株块根重、木薯块根鲜重、经济效益分别比处理2增加51.36%、11.14%、18.48%、21.57%、18.76%、34.88%、40.04%、31.89%、9033.8元/ha,差异均达显著（P〈0.05）或极显著水平（P〈0.01）。【结论】采用生物有机肥＋测土配方肥＋盖膜微集雨技术,可为木薯高产稳产的生长发育提供及时、持续、平衡的养分供应与水肥条件,并可显著改善土壤理化性状。

3种不同类型土壤对木薯产量影响试验分析

分别在疏松类型土壤、渍水类型土壤、板结类型土壤里种植木薯,探讨3种类型土壤对木薯产量的影响结果,并提出了相应的技术措施,为平南县今后发展木薯生产、促进木薯产业可持续发展积累技术经验。

木薯不同种植方式的土壤保持效应

采用随机区组试验,研究了坡耕地木薯不同种植方式对土壤保持及木薯产量的影响。结果表明:各处理的土壤流失量均极显著少于对照;除"犁耙—施肥—起畦"和"犁耙—施肥—不起畦—高度分枝品种"外,其它处理的木薯块根产量均显著或极显著高于对照;处理的木薯茎叶产量均极显著高于对照。"犁耙—施肥—不起畦—间种花生"的土壤流失量极显著少于其它处理,木薯产量也较高。坡耕木薯地土壤流失量与降雨量呈显著或极显著正相关。降雨是木薯坡耕地土壤流失的主要原动力,"犁耙—施肥—不起畦—间种花生"是木薯坡耕地土壤保持的首选种植模式。

鲜食木薯品比试验

利用西场1号、沙田面包木薯、华南12号、与对照种华南9号进行品比试验,通过品比试验,沙田面包木薯具有高产量、高淀粉、含氢氰酸低等优势,作为鲜食木薯品种,值得推广种植。

Effects of Different Cultivation Methods on Growth, Yield and Quality of Cassava

The research explored effects of cultivation methods on growth, yield and quality of cassava. The results showed that the mulching treatment by direct seed- ing, the mulching treatment by transplanting, and the exposed treatment by trans- planting performed excellently in bringing seedling stage forward, improving germina- tion rate, yield and quality. For example, seedling emergence stages were 36, 31 and 31 d earlier; germination rates improved by 19.24%, 14.29% and 14.29%; yields grew by 41.98%, 26.72% and 11.45%; starch contents increased by 3.50%, 2.10% and 1.40%, respectively. Therefore, cassava in the mulching treatment by direct seeding is characterized by earlier seedling emergence stage, high germination rate, high yield and quality.

Comparative Experiment on Fertilizer Tolerance and Yielding Ability of Cassava in Hunan

[Objective] In order to explore the yield potential of cassava, the responses of new cassava varieties to fertilizer quantity was investigated. [Method] A comparative experiment was carried out on 5 new fertilizer-tolerant high-yield cassava varieties（Guire 8, Guire 9, Guire 10, Xinxuan 048 and Guiken 09-26） with the normal-level fertilization groups of these varieties as controls. [Result] The results showed that：（1） increasing fertilizers could significantly improve the stem and leaf yield of cassava;（2） increasing fertilizers could reduce the dry matter content of cassava; and（3） different varieties differed in fertilizer tolerance, and the fertilizing amount should be determined according to specific varieties. [Conclusion] Guire 10 and Xinxuan 048 are suitable for being cultivated at a high fertilizer level, and the remaining three varieties（Guiken 09-26, Guire 8 and Guire 9） are suitable for being cultivated at a normal fertilizer level.

Agronomic Evaluation of New Cassava Varieties Introduced to Farmers in Nigeria

In 2005, 10 new cassava varieties were officially selected and released to farmers in Nigeria for high root yield, high dry matter content and acceptability for food. This work compared in three on farm locations, the root and stem yield of these varieties together with an old improved variety currently in farmers＇ field. In all the locations, root yield of all the new materials were significantly higher （P 〈 0.05） than the old improved variety. The root yields of the new varieties were between 40%-50% higher than the old improved varieties. Overall yield advantages of the new materials over the old improved material ranged between 40%-150%. Stem yield figures showed significant variations with few of the new varieties producing higher stem yield in comparison with the old improved variety due to inherent growth pattern. Figures for tuber girth and node numbers per unit of stem were similar. The high yield levels of the new varieties might lead to high demand for stems indicating the likely wider spread and higher demand for varieties with high stem yield potentials.

Effects of Application of Cassava Alcohol Anaerobic Fermentation Liquid and Mulching of Film on Overwintering and Next Year's Growth and Yield of Banana

The effects of application of cassava alcohol anaerobic fermentation liquid and mulching of film on overwintering and next year's growth and yield of banana were investigated in this study.The results showed that the application of cassava alcohol anaerobic fermentation liquid with COD concentration of 1 200-2 000 mg/L(900 m^3/hm^2) and mulching of film significantly increased the soil organic matter and available potassium contents in banana orchard,improved the cold resistance of banana seedlings,increased the pseudostem height,pseudostem circumference,green leaf number and chlorophyll content of next year's banana seedlings,brought the flower bud emergence period and harvest period forward,and significantly increased the yield per plant.

Studies on the effects of bio-organic fertilizer on the physical and chemical characteristics of soil and the yield of cassava＊

Bio-organic fertilizer is a new type of fertilizer which have advantages of both organic manure and fertilizer. This study investigated the effects of bio-organic fertilizer on the growth and yield of cassava and the soil fertility. The study was carried out in the period of 2004-2005 and the material was cassava cultivar FUXUAN01. The bio-organic fertilizers were applied as basic fertilizers on four different levels of 450 kg/hm^2, 600 kg/hm^2, 750 kg/hm^2, 900 kg/hm^2 in this experiment. The growth of stem and leaf, the yield of earthnut and the starch content of tuber root of cassava and the unit weight, the hole percent, the content of organic matters, nitrogen, phosphorus and potassium, microbes, the activity of soil urease and invertase were analyzed during the experiment. The results showed that not only can the bio-organic fertilizer promote the growth of cassava stems and leaves, increase the chlorophyll content and the photosynthesis of leaves, improve the physiological metabolism of cassava, and strengthen physiological function of anti-senility, promote the transformation from photosynthetic organism to tuber root and increase the yield and starch content in the tuber root of cassava, but also decrease the soil unit weight, increase the hole percent of soil, promote microbe activity in the soil, increase the activity of soil urease and invertase, promote the availability of nutrients, increase the content of organic matters, available nitrogen, phosphorus and potassium, and increase the utilization rate of fertilizer. It was an effective way to apply the bio-organic fertilizer to increase the yield and starch content in the tuber root of cassava, improving the physical and chemical characters of soil and increasing the soil fertility.

Impact of Planting Position and Planting Material on Root Yield of Cassava （Manihot esculenta Crantz）

Cassava （Manihot esculenta Crantz） is a perennial woody shrub with an edible root, which grows in tropical and subtropical areas of the world. In Africa, cassava provides a basic daily source of dietary energy. It plays an important role in food security and incomes of many rural households in the southern Ethiopia. However, information available on production practices of cassava for the region is insufficient. Hence, field experiment was conducted at Awassa Agricultural Research Center for two successive cropping seasons from 2004 to 2006 to investigate the response of cassava to planting position and planting material. The treatments used were three planting positions （slant, vertical and horizontal） and five planting materials （main stem top part, main stem middle part, main stem bottom part, branch stake top part and branch stake bottom part） were combined in factorial arrangement and laid out in randomized complete block design with three replications. The result revealed that root yield was significantly （P 〈 0.05） affected by the interaction effects of the planting position and planting material. The highest yield （25.2 ton ha^-1） was obtained from the main stem top part planted in slant position whereas the least yield （6.5 ton ha^-1） was obtained from main stem bottom part planted in horizontal position. Based on the findings of this study, areas like Awassa with moderate rainfall slant and vertical planting of main stem top and middle parts could be used as planting material.

Effect of Different Organic Nutrient Sources and Two NPK Rates on the Performance and Nutrient Contents of A Newly Released Cassava Variety

A field experiment was conducted to determine the response of a newly released cassava variety （TMS 98/0510） in Nigeria to three sources of organic manure （poultry waste, pig dung and goat dung at 10 t/ha）, two levels inorganic fertilizer （N：P：K 15：15：15 at 200 and 400 kg/ha） and a control treatment. The six treatments were compared in a randomized complete block design with three replications. Data were collected on yields and yield related agronomic and morphological traits. Data were also collected on soil nutrient content at planting and the content of N, P, K, Ca and Mg in the leaf stem and roots. The results showed that the soil used in this experiment was low in organic matter and other nutrients except available P. Inorganic and organic fertilizers significantly increased leaf area, however yield and growth related traits like plant height, number of leaves, stem yield, tuber girth, number of roots and harvest index were not significantly different among the treatments. Contrary to expectations manure and fertilizer treatments did not increase fresh root yield in this cassava variety. They did not also influence the content of N, P, K, Ca and Mg in the stem, leaf and root. This response suggests that cassava varieties bred for farmers＇ conditions in Nigeria, which are inherently low in soil nutrients, may not respond to additional nutrient input. Breeders should therefore select cassava for dual adaptation to low and high nutrient levels in the soil to meet the needs of a wider spectrum of farmers and to justify government and extension support for the use of input by farmers in Nigeria.