RESPONSES OF MYZUS PERSICAE AND BREVICORYNE BRASSICAE TO LEAF AGE AND WATER STRESS IN BRUSSELS SPROUTS GROWN IN POTS

Se han identificado las siguientes especies procedentes del valle de cañete : Aphis citicola, A.craccivora, A. fabae, A.gossypii, Brevicoryne,brassicae, Lypaphis erysimi Macrosiphum euphorbiae, M. rosae, Myzus persicae, Riopalosiphum maidis, R. padi, toxoptera aurantii, T. citricidus y tuberolachnus salignus Todos los áfidos identificados representan especies de importancia económica, excepto el último.

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Susceptibility of Myzus persicae, Brevicoryne brassicae and Nasonovia ribisnigri to Fungal Biopesticides in Laboratory and Field Experiments

Insects ◽

10.3390/insects11010055 ◽

2020 ◽

Vol 11 (1) ◽

pp. 55

Author(s):

Gill Prince ◽

Dave Chandler

Keyword(s):

Field Experiment ◽

Myzus Persicae ◽

Field Experiments ◽

Brevicoryne Brassicae ◽

Vegetable Crops ◽

Potato Aphid ◽

Cabbage Aphid ◽

Nasonovia Ribisnigri ◽

Fungal Biopesticides ◽

Peach Potato Aphid

The aim of this study was to evaluate the potential of entomopathogenic fungi (EPF) for the control of aphid pests of field vegetable crops. Four biopesticides based on the EPF Beauveria bassiana (Botanigard ES and Naturalis L), Cordyceps fumosorosea s.l. (Preferal WG), and Akanthomyces dipterigenus (Vertalec) were evaluated in a laboratory bioassay against peach-potato aphid Myzus persicae, cabbage aphid Brevicoryne brassicae, and currant-lettuce aphid Nasonovia ribisnigri. There was significant variation in the spore dose provided by the products, with Botanigard ES producing the highest dose (639 viable spores per mm2). Botanigard ES also caused more mortality than the other products. Combining Vertalec with the vegetable oil-based adjuvant Addit had an additive effect on the mortality of B. brassicae. All fungal products reduced the number of progeny produced by M. persicae but there was no effect with B. brassicae or N. ribisnigri. When aphid nymphs were treated with Botanigard ES and Preferal WG, both products reduced population development, with up to 86% reduction occurring for Botanigard ES against M. persicae. In a field experiment, Botanigard ES sprayed twice, at seven-day intervals, against B. brassicae on cabbage plants, reduced aphid numbers by 73%. In a second field experiment with B. brassicae, M. persicae, and N. ribisnigri, Botanigard ES reduced populations of B. brassicae and N. ribisnigri but there was no significant effect on M. persicae.

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Differential responses between mature and young leaves of sunflower plants to oxidative stress caused by water deficit

Ciência Rural ◽

10.1590/s0103-84782010000600008 ◽

2010 ◽

Vol 40 (6) ◽

pp. 1290-1294 ◽

Cited By ~ 11

Author(s):

Inês Cechin ◽

Natália Corniani ◽

Terezinha de Fátima Fumis ◽

Ana Catarina Cataneo

Keyword(s):

Water Stress ◽

Gas Exchange ◽

Leaf Gas Exchange ◽

Intercellular Co2 Concentration ◽

Leaf Age ◽

Co2 Concentration ◽

Mature Leaves ◽

Young Leaves ◽

Mda Content ◽

Gas Exchange Characteristics

The effects of water stress and rehydration on leaf gas exchange characteristics along with changes in lipid peroxidation and pirogalol peroxidase (PG-POD) were studied in mature and in young leaves of sunflower (Helianthus annuus L.), which were grown in a greenhouse. Water stress reduced photosynthesis (Pn), stomatal conductance (g s), and transpiration (E) in both young and mature leaves. However, the amplitude of the reduction was dependent on leaf age. The intercellular CO2 concentration (Ci) was increased in mature leaves but it was not altered in young leaves. Instantaneous water use efficiency (WUE) in mature stressed leaves was reduced when compared to control leaves while in young stressed leaves it was maintained to the same level as the control. After 24h of rehydration, most of the parameters related to gas exchange recovered to the same level as the unstressed plants except gs and E in mature leaves. Water stress did not activated PG-POD independently of leaf age. However, after rehydration the enzyme activity was increased in mature leaves and remained to the same as the control in young leaves. Malondialdehyde (MDA) content was increased by water stress in both mature and young leaves. The results suggest that young leaves are more susceptible to water stress in terms of gas exchange characteristics than mature leaves although both went through oxidative estresse.

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