. Manual of fruit insects. a similar injury tograpes in presence in avineyard is first in-dicated by abnor-mally enlarged, yel-lowish or darkreddish blossombuds (Fig. 378)which fail to openand drop off aboutthe normal time forblossoming. Open-ing one of these Fig. 378. — Enlarged blossom buds infested with j u J midge larvaj, normal blossom buds at the right. enlarged DUClS, It will be found tocontain a number of small whitish or yellowish maggots fromtV to tV inch in length (Fig. 379). From 10 to 60 per cent ofthe buds are some-times destroyed,giving the clustersa very thin andragg
. Manual of fruit insects. a similar injury tograpes in presence in avineyard is first in-dicated by abnor-mally enlarged, yel-lowish or darkreddish blossombuds (Fig. 378)which fail to openand drop off aboutthe normal time forblossoming. Open-ing one of these Fig. 378. — Enlarged blossom buds infested with j u J midge larvaj, normal blossom buds at the right. enlarged DUClS, It will be found tocontain a number of small whitish or yellowish maggots fromtV to tV inch in length (Fig. 379). From 10 to 60 per cent ofthe buds are some-times destroyed,giving the clustersa very thin andragged appearance,and thus decreas-ing considerably themarket value of thecrop. The parent insectis a delicate two-winged midge witha yellowish bodyand straw coloredlegs (Fig. 380). The. Fig. 379. - Grape blossom buds opened to showlarvae inside, enlarged. GRAPE INSECTS 439 inch in length and the male a little smaller. The flies emergefrom the ground in the latter part of May just as some ofthe blossom buds of such early varieties as Moore, Earlyand Worden begin to show a small opening at the tip causedby a spreading of the petals. The female deposits her minute,grayish, elongate, slightly curved eggs in the interior ofthe bud by meansof an extensile fleshyovipositor insertedthrough this open-ing in the apex ofthe bud. From afew to seventy mag-gots may be foundin a single bud, buttwenty-five is aboutthe average in ayear of heavy infes-tation. The infestedbuds contain awatery fluid inwhich the maggotslive. Such budsbecome greatlyswollen, often threetimes as large
Size: 1699px × 1470px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectbenefic, bookyear1915
