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Assessing cotton defoliation, regrowth control and root rot infection using remote sensing technology

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International Journal of agricultural and Biological Engineering 2011年第4期4卷 1-11页

作者： Chenghai Yang Shoil M.Greenberg James H.Everitt Carlos J.Fernandez USDA-ARS Kika de la Garza Subtropical Agricultural Research CenterWeslacoTexas 78596USA Texas AgriLife research and Extension center Corpus ChristiTexas 78406USA

Cotton defoliation and post-harvest destruction are important cultural practices for cotton production.Cotton root rot is a serious and destructive disease that affects cotton yield and lint quality.This paper presents an overview and summary of the methodologies and results on the use of remote sensing technology for evaluating cotton defoliation and regrowth control methods and for assessing cotton root rot infection based on published studies.Ground reflectance spectra and airborne multispectral and hyperspectral imagery were used in these studies.Ground reflectance spectra effectively separated different levels of defoliation and airborne multispectral imagery permitted both visual and quantitative differentiations among defoliation treatments.Both ground reflectance and airborne imagery were able to differentiate cotton regrowth among different herbicide treatments for cotton stalk destruction.Airborne multispectral and hyperspectral imagery accurately identified root rot-infected areas within cotton fields.Results from these studies indicate that remote sensing can be a useful tool for evaluating the effectiveness of cotton defoliation and regrowth control strategies and for detecting and mapping root rot damage in cotton fields.Compared with traditional visual observations and ground measurements,remote sensing techniques have the potential for effective and accurate assessments of various cotton production operations and pest conditions.

关键词： remote sensing cotton defoliation regrowth control root rot reflectance spectrum airborne multispectral imagery airborne hyperspectral imagery

Sublethal effects of malathion on boll weevil （Coleoptera： Curculionidae） fecundity when maintained on cotton squares or artificial diet

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Insect Science 2006年第4期13卷 287-292页

作者： JOHN SCOTT ARMSTRONG ALlaN T. SHOWLER MAMOUDOU SETAMOU SHOIL GREENBERG Beneficial Insects Unit Integrated Farming and Natural Resources research Unit Kika de la Garza Subtropical Agricultural Research Center USDA-ARS Texas A&M University Citrus center Welascao Texas USA

Mated 3-day-old female boll weevils, Anthonomus grandis grandis Boheman, reared from field-infested cotton （Gossypium hirsutum L.） squares were topically treated with an estimated LD50 of malathion （2μg） to assess its effects on fecundity, oviposition, and body fat condition. Two different food sources, cotton squares and artificial diet, were assessed in malathion-treated and nontreated （control） weevils. The LD50 caused ≈ 50% mortality in the square-fed malathion treatment, but the artificial diet-fed malathion-treated weevils were less susceptible. LD50 survivors fed on the squares produced ≥ 9 times more chorionated eggs in the ovaries and oviposited ≥ 19-fold more than survivors fed artificial diet, regardless of the malathion treatment. Boll weevils that survived a 2μg LD50 malathion and also fed squares were ≈4.5-fold leaner than diet-fed weevils. Our findings demonstrate that non-resistant boll weevils surviving a sublethal dose of malathion will reproduce without any delay or significant loss in fecundity, and the food source for which boll weevils are maintained when conducting these assays will directly affect the results. The significance of these findings and how they are related to the final stages of eradicating the boll weevil from the US are discussed.

关键词： Anthonomus grandis grandis boll weevil fecundity malathion sublethal

集成GPS和GIS技术的变量灌溉控制系统(英文)

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农业工程学报 2006年第10期22卷 134-138页

作者：杨青庞树杰杨成海李敏通李勇军杨术明西北农林科技大学机械与电子工程学院 USDA-ARS kika de la garza subtropical agricultural research center WeslacoTexas78596USA

结合中国现实国情,应用先进的单片机、G IS、GPS以及变量控制技术,设计了一种经济实用、先进的变量灌溉控制系统。系统设计采用AT 89C 51单片机作为系统微处理器,Jup iter GPS OEM二次开发作为GPS接收机,IC卡作为G IS数据传递媒体,并根... 详细信息

结合中国现实国情,应用先进的单片机、G IS、GPS以及变量控制技术,设计了一种经济实用、先进的变量灌溉控制系统。系统设计采用AT 89C 51单片机作为系统微处理器,Jup iter GPS OEM二次开发作为GPS接收机,IC卡作为G IS数据传递媒体,并根据矢量法提出一种简单快速的田间定位和数据查询算法。灌溉机在田间工作时,系统可从GPS OEM得到位置信息,进行地块识别和位置判断;然后根据位置信息从IC卡的G IS信息中查询土壤属性数据或处方数据,结合机械行走速度、施水幅宽等进行运算,得出某一时刻的灌水量;最后向控制器发出指令,实现变量节水灌溉。田间和实验室模拟试验结果表明,自行研制的低成本GPS OEM接收机,可获得与A g GPS132相当的定位精度,控制系统能根据处方图的不同需水量,通过电磁阀驱动电路得到变化的输出,实现自动变量施水,系统也能根据需水量进行手动灌溉。

关键词：变量灌溉控制系统处方图 GPS OEM GIS

Economic and Environmental Impact Transgenically Modified Cotton Comparative with Synthetic Chemicals for Insect Control

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Journal of agricultural Science and Technology(B) 2012年第7期2卷 750-757页

作者： Shoil Greenberg Jaime Alejandro Mamoudou Setamou Beneficial Insect research Unit Kika de la Garza Subtropical Agricultural Research Center Agricultural Research ServiceUnited States Department of Agriculture Weslaeo Texas 78596 USA department of Entomology Texas A&M University-Kingsville Citrus Center Weslaco Texas 78596 USA

This article combines both a review of the literature and original data from our research. The comparative efficacy of Bacillus thuringiensis (Berliner) traits Bollgard, Bollgard II, WideStrike, and non-Bt expressing cotton, Gossypium hirsutum L., for control of the noctuid complex of bollworm, Helicoverpa zea (Boddie); fall armyworm, Spodoptera frugiperda (J. E. Smith); beet armyworm, Spodoptera exigua (Hubner); and cabbage looper, Trichoplusia ni (Hubner), were evaluated in the Lower Rio Grande Valley of Texas during 2005-2009. Noctuid larval survival and damage to leaves on non-Bt cotton were 3.6-fold greater than on Bollgard II or WideStrike cotton and 1.5-fold greater than on cotton varieties with the Bollgard trait. Transgenic cotton has reduced the need for conventional insecticides with benefits to human health and the environment. The revenue differences between Bt and conventional cotton for last four years in LRGV of Texas was 214.3$/ha and profit about 94.9$/ha. We also analyzed cotton noctuid losses between Bt and conventionally grown cotton in the USA summary of all states and Texas summary of all regions.

关键词：转基因棉花 Bt棉花环境影响病虫害防治化学物质人工合成甜菜夜蛾苏云金芽孢杆菌

利用计算机模拟采样确定合理的土壤采样密度(英文)

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农业工程学报 2006年第8期22卷 145-148页

作者：王宏斌杨青刘志杰杨成海西北农林科技大学机械与电子工程学院杨凌712100 USDA-ARS kika de la garza subtropical agricultural research center WeslacoTexasUSA

为了解决土壤采样中精度与经济性的平衡问题，利用计算机模拟采样研究了规则网格土壤采样时合理的采样点密度。首先构造了一个数学扩散模型，设置2～4个种子在一个100×100网格（1×1单位）的不同地方，根据扩散模型进行扩散和叠加，生... 详细信息

为了解决土壤采样中精度与经济性的平衡问题，利用计算机模拟采样研究了规则网格土壤采样时合理的采样点密度。首先构造了一个数学扩散模型，设置2～4个种子在一个100×100网格（1×1单位）的不同地方，根据扩散模型进行扩散和叠加，生成模拟的土壤属性分布地图，其结果可很好地模拟某些土壤属性的分布。利用计算机按照不同的网格单元尺寸（如3×3，5×5，7×7等）进行采样，之后利用采样值进行IDW插值处理，将数据点恢复到原始的10000个，并把插值结果与原始值进行比较即可得到采样误差。研究结果表明，当采样网格单元尺寸为属性地图输出栅格单元尺寸的11倍和17倍时，相对采样误差分别为10％和15％。合理的采样密度可以根据允许的采样误差及要求的属性地图输出栅格单元尺寸而定。

关键词：优化采样点密度计算机模拟采样数学扩散模型采样误差

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变量穴施水穴播机的变量施水数学模型

农业机械学报 2009年第S1期40卷 41-44页

作者：杨术明杨青杨成海西北农林科技大学机械与电子工程学院陕西杨凌712100 宁夏大学机械工程学院银川750021 USDA-ARS kika de la garza subtropical agricultural research center

根据变量穴施水穴播机使用要求,建立了最小施水量数学模型和电磁阀控制时间数学模型。在自行开发的变量穴施水穴播机上进行静态试验,通过改变水箱水量、施水时间,获得不同的施水量。分别采用回归分析和人工神经网络预测2种方法,研究了... 详细信息

根据变量穴施水穴播机使用要求,建立了最小施水量数学模型和电磁阀控制时间数学模型。在自行开发的变量穴施水穴播机上进行静态试验,通过改变水箱水量、施水时间,获得不同的施水量。分别采用回归分析和人工神经网络预测2种方法,研究了水箱水量、施水时间及施水量之间的关系,建立了电磁阀控制时间的数学模型。回归试验表明,在水箱水量处于满箱、半箱和1/8箱容积3种状态时,所对应的电磁阀控制时间线性回归模型的调整判定系数R2依次为0.992、0.991和0.998,具有较高的拟合度。对回归方程进行的F检验结果表明,F计算值远大于查表值,回归方程极显著。采用2-5-1型拓扑结构的人工神经网络对施水时间进行预测,结果表明,拟合的最大偏差为3.95 ms,平均偏差仅为1.46 ms,网络结构具有较高的预测精度。

关键词：穴施水穴播机变量施水数学模型人工神经网络

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精细农业信息采集通用软硬件平台设计

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