Collection of Phloem Sap in Phytoplasma-Infected Plants

1. A study has been made of the factors involved in the uptake of phloem sap by Tuberolachnus salignus (Gmelin) feeding on the stems of various Salix spp. 2. A method has been developed for maintaining the parthenogenetic viviparous forms of T. salignus in culture throughout the year. 3. It has been established that during normal feeding T. salignus have the tips of their stylets inserted into the phloem sieve-tubes of the host plant. 4. The phloem sieve-tube sap of intact and turgid willow stems is under considerable pressure. This pressure forces the sieve-tube mp up the stylet food canal of feeding aphids, and also causes the sieve-tube sap to exude for many hours from the cut end of embedded stylet bundles. 5. Intact and feeding T. salignus rely almost entirely on this pressure to maintain their normal rate of eieve-tube sap uptake. The aphids must, however, swallow actively in order to ingest.

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Development of Bemisia tabaci (Gennadius,1889) biotype B on Lycopersicon spp. genotypes

Scientia Agricola ◽

10.1590/s0103-90162002000400007 ◽

2002 ◽

Vol 59 (4) ◽

pp. 665-669 ◽

Cited By ~ 12

Author(s):

Fancelli Marilene ◽

José Djair Vendramim

Keyword(s):

Antibiotic Resistance ◽

Host Plant ◽

Bemisia Tabaci ◽

Developmental Time ◽

Phytophagous Insects ◽

Insect Development ◽

Phloem Sap ◽

Direct Damage ◽

Antibiotic Effect ◽

Biotype B

Whiteflies are phytophagous insects, whose nymphs and adults suck the phloem sap, causing direct damage due to host plant weakness. In tomato (Lycopersicon spp.) crops, they are important vectors of limiting fitoviruses. The objective of this study was to determine the effects of Lycopersicon spp. genotypes on Bemisia tabaci (Gennadius, 1889) biotype B development under greenhouse conditions. The evaluated genotypes were LA462 (L. peruvianum), LA716 (L. pennellii), LA1584 (L. pimpinellifolium), LA1609 (L. peruvianum), LA1739 (L. hirsutum), P25 (L. esculentum), PI134417 (L. hirsutum f. glabratum) and Santa Clara (L. esculentum). LA716 was non-preferred for oviposition by the whitefly, which suggests an antixenotic effect. LA1584 showed an antibiotic resistance because nymphal survival was reduced and nymphal developmental time was increased. Antixenotic resistance was observed in LA1739 and PI134417, based on a reduction of oviposition. PI134417 also reduced nymphal survival, which suggests an antibiotic effect, but LA1739 was suitable for insect development. LA1609 was highly preferred for oviposition, however it reduced insect survival. P25 and Santa Clara (L. esculentum) were highly preferred for oviposition.

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The green peach aphid Myzus persicae perform better on pre-infested Chinese cabbage Brassica pekinensis by enhancing host plant nutritional quality

Scientific Reports ◽

10.1038/srep21954 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 24

Author(s):

He-He Cao ◽

Hui-Ru Liu ◽

Zhan-Feng Zhang ◽

Tong-Xian Liu

Keyword(s):

Chinese Cabbage ◽

Myzus Persicae ◽

Green Peach Aphid ◽

Marker Genes ◽

Plant Leaves ◽

Resistance Level ◽

Aphid Infestation ◽

Phloem Sap ◽

Brassica Pekinensis ◽

Plant Nutritional Quality

Abstract The green peach aphid, Myzus persicae Sulzer, is a notorious pest on vegetables, which often aggregates in high densities on crop leaves. In this study, we investigated whether M. persicae could suppress the resistance level of Chinese cabbage Brassica pekinensis. M. persicae performed better in terms of weight gain (~33% increase) and population growth (~110% increase) when feeding on previously infested (pre-infested) Chinese cabbage compared with those on non-infested plants. However, when given a choice, 64% of the aphids preferred to settle on non-infested leaves, while 29% of aphids chose pre-infested leaves that had a 2.9 times higher concentration of glucosinolates. Aphid feeding significantly enhanced the amino acid:sugar ratio of phloem sap and the absolute amino acid concentration in plant leaves. Aphid infestation significantly increased the expression levels of salicylic acid (SA) marker genes, while it had marginal effects on the expression of jasmonate marker genes. Exogenously applied SA or methyl jasmonate had no significant effects on M. persicae performance, although these chemicals increased glucosinolates concentration in plant leaves. M. persicae infestation increase amino acid:sugar ratio and activate plant defenses, but aphid performed better on pre-infested plants, suggesting that both nutrition and toxics should be considered in insect-plant interaction.

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Inhibition of α-glucosidase activity by N-deoxynojirimycin analogs in several insect phloem sap feeders

Insect Science ◽

10.1111/1744-7917.12229 ◽

2015 ◽

Vol 23 (1) ◽

pp. 59-67 ◽

Cited By ~ 3

Author(s):

Marina Katzman Ya'kobovitz ◽

Terry D. Butters ◽

Ephraim Cohen

Keyword(s):

Phloem Sap ◽

Glucosidase Activity

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Transport of Resistance - Inducing Sterols in Phloem Sap of Barley§

Zeitschrift für Naturforschung C ◽

10.1515/znc-2000-11-1216 ◽

2000 ◽

Vol 55 (11-12) ◽

pp. 948-952 ◽

Cited By ~ 5

Author(s):

Axel T. Lehrer ◽

Dereje Dugassa-Gobena ◽

Stefan Vidal ◽

Karlheinz Seifert

Keyword(s):

Transport System ◽

Phloem Sap ◽

Sterol Transport ◽

Sap Feeding

After root application of [7α-3H]-7β-hydroxysitosterol and [3α,6β-3H2]-6α-hydroxylathosterol these sterols could be detected in the leaves and phloem sap feeding aphids. These results imply that the phloem sap is a sterol transport system in barley plants.

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