Infestation of Germplasm Lines and Cultivars of Cotton in Arizona by Whitefly Nymphs (Homoptera: Aleyrodidae)

Seasonal abundance of whitefly nymphs, primarily sweetpotato whitefly, Bemisia tabaci (Gennadius), and bandedwinged whitefly, Trialeurodes abutilonea (Haldeman), on leaves of germplasm lines and cultivars of cotton, Gossypium hirsutum L., were determined in field plots at Maricopa, AZ, in 1987. In general, the germplasm lines with the greatest numbers of leaf trichomes (range 2 to 98 per cm2) had the greatest numbers of nymphs (range 0.4 to 11.3 nymphs per leaf on 23 September). The okra-leaf characteristic did not have a consistent effect on the numbers of nymphs. Deltapine 20, Centennial, and Stoneville 506 cultivars planted on 30 April had significantly greater infestations (range 20.3 to 121.3 nymphs per leaf) on 16 October than did the same cultivars planted 21 May (range 4.5 to 53.0) or 11 June (range 7.0 to 31.5). The nectariless okra-leaf line WC-12NL and cultivar Deltapine 61 had 1.1 and 1.5 nymphs per leaf on 22 September, respectively, not significantly different.

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Reflectance of single leaves and field plots ofcycocel-treated cotton (Gossypium hirsutum L.) in relation to leaf structure

Remote Sensing of Environment ◽

10.1016/s0034-4257(70)80011-6 ◽

1970 ◽

Vol 1 (2) ◽

pp. 103-107 ◽

Cited By ~ 4

Author(s):

H.W. Galisman ◽

W.A. Allen ◽

V.I. Myers ◽

R. Cardenas ◽

R.W. Leamer

Keyword(s):

Gossypium Hirsutum ◽

Leaf Structure ◽

Gossypium Hirsutum L ◽

Field Plots

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Sub-Lethal Effects of Lecanicillium lecanii (Zimmermann)-Derived Partially Purified Protein and Its Potential Implication in Cotton (Gossypium hirsutum L.) Defense against Bemisia tabaci Gennadius (Aleyrodidae: Hemiptera)

Agriculture ◽

10.3390/agriculture11080778 ◽

2021 ◽

Vol 11 (8) ◽

pp. 778

Author(s):

Yusuf Ali Abdulle ◽

Talha Nazir ◽

Samy Sayed ◽

Samy F. Mahmoud ◽

Muhammad Zeeshan Majeed ◽

...

Keyword(s):

Gossypium Hirsutum ◽

Bemisia Tabaci ◽

Expression Profiles ◽

Control Technique ◽

Systemic Resistance ◽

Gossypium Hirsutum L ◽

Potential Implication ◽

Lecanicillium Lecanii ◽

Fecundity Rate ◽

Cotton Plants

Whiteflies, Bemisia tabaci Gennadius (Aleyrodidae: Hemiptera), are a polyphagous economically destructive pest of several solanaceous crops around the world. Many secondary metabolites are synthesized by different biotrophic and necrotrophic fungi which are capable of inducing systemic resistance in plants against various phytophagous pests. The present laboratory work demonstrated the anti-insect impact of a protein extracted and purified partially from an entomopathogenic fungus (EPF) Lecanicillium lecanii (Zimmermann) against B. tabaci. Three different concentrations (i.e., 7.43, 11.15, and 22.31 μg mL−1) of this protein were bioassayed to assess its effect on the fecundity rate of B. tabaci on cotton (Gossypium hirsutum L.) plants. Furthermore, the possible implication of this fungal protein in defense pathways of cotton plants was evaluated by determining the expression profiles of salicylic acid (SA) and jasmonic acid (JA) pathways related to major genes through reverse transcription qPCR (RT-qPCR). According to the results, all protein concentrations exerted a significant (F3, 252 = 62.51; p ≤ 0.001) and negative impact on the fecundity rate of B. tabaci females. At the highest protein concentration (22.31 μg mL−1), the minimum rate of fecundity (i.e., 2.46 eggs female−1day−1) of B. tabaci was noted on the seventh day, whereas fecundity rates for the other two protein concentrations (i.e., 11.15 and 7.43 μg mL−1) were, respectively, 3.06 and 3.90 eggs day−1 female−1. The maximum rate of fecundity (6.01 eggs female−1day−1) was recorded in untreated (control) treatments. In addition, the foliar application of L. lecanii derived protein significantly upregulated all SA linked genes (OPR3, PPO1 and COI1) and slightly triggered up the JA linked genes (LOX1, UBQ7 and AOS) in the cotton plants. These findings revealed that this L. lecanii extracted partially purified protein triggered systemic resistance against B. tabaci in the cotton plants, proposing its putative effectiveness as an innovative biological control technique against B. tabaci and other phloem-feeding hemipteran pests. Nevertheless, further investigations such as purification and molecular and functional characterization of this L. lecanii-derived partially purified protein are required.

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Preferência de Bemisia tabaci biótipo B em linhagens mutantes de algodoeiro

Ciência Rural ◽

10.1590/s0103-84782008000100010 ◽

2008 ◽

Vol 38 (1) ◽

pp. 59-64

Author(s):

Francisco das Chagas Vidal Neto ◽

Fanuel Pereira da Silva ◽

Ervino Bleicher ◽

Francisco Ivaldo Oliveira Melo

Keyword(s):

Gossypium Hirsutum ◽

Bemisia Tabaci ◽

Gossypium Hirsutum L

Os efeitos de caracteres mutantes morfológicos do algodoeiro (Gossypium hirsutum L. r. latifolium Hutch.): folha okra, bráctea frego e planta vermelha, em relação à resistência à mosca-branca (Bemisia tabaci biótipo B Hemiptera: Aleyrodidae), foram avaliados em experimentos com ou sem chance de escolha. Os experimentos foram conduzidos em casa-de-vegetação, no delineamento de blocos ao acaso, em fatorial 23 + 1, com quatro repetições. O mutante com a característica planta vermelha foi menos atrativo e menos preferido para oviposição, em relação à planta verde, em ambos os ensaios, com ou sem escolha. Não houve preferência quanto à forma da folha e ao tipo de bráctea.

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