278 



Jack (R. W.). Notes on the Maize Stalk Borer or "Top Worm."— 



Rhodesia Agric. Jl., Salisbury, xix, no. 1, February 1922, 

 pp. 87-88. 



The maize stalk-borer [Busseola fusca, Hmps.] has been much more 

 abundant than during the previous season owing to late planting 

 and weather conditions, as well as a variety of obscure factors. The 

 results of previous observations have again been confirmed [R. A.E., A, 

 vi, 153], and planting in the neighbourhood of Salisbury should be 

 done between 4th December and Christmas. Whether these dates 

 would be somewhat earlier for lower altitudes is not yet certain. 

 The early planting of a number of rows of maize or kaffir corn as a trap 

 crop is also advocated. 



Patterson (W. H). Report on Entomological and Mycological Work, 

 Aburi, December 31st, 1920. — Gold Coast Rept. Agric. Dept., 



1920, Accra, 1922, p. 17. 



Owing to the lack of cultivation and unfavourable conditions for 

 the cacao crop, the cacao thrips is rapidly increasing its sphere of 

 damage. Pests of other crops remain as previouslj^ reported. 

 Eriophyes gossypii. Banks (leaf-blister cotton mite) does not appear 

 to have been imported from Jamaica with cotton seed. Larvae of 

 Pseiidagrilus sophorae, L., did much damage to Hibiscus sinensis, 

 but the beetle did not attack neighbouring cotton plants. All infested 

 stems should be removed and burned, 



Briggs (G.). Report of the Agronomist and Horticulturist. — Rept. 

 Guam Agric. Expt. Sta., 1920, Washington, D.C., 21st November 



1921, pp. 15-64, 4 plates. [Received 22nd March 1922.] 



Maize is considerably damaged by insect pests in Guam. Marasmia 

 trapezalis (leaf-folder) is destructive in the larval stage, feeding on 

 the young leaves, and appears to occur throughout the year. The 

 European corn-borer [Pyrausta nubilalis] is present in large numbers 

 on the island, and is most noticeable on mature maize. The first 

 sign of the presence of the moth is the breaking off of the tassel and the 

 protrusion of frass from the stalks. It has also attacked sorghum, 

 rice and other plants. It was first found causing considerable damage 

 in 1917, but it is not known how or when it was introduced into Guam. 

 The burning of all stalks and cobs as soon as they are dry has been 

 recommended as a remedial measure, and so far no others are known. 

 Aphis maidis attacks maize in nearly all stages of growth, and leaf- 

 hoppers are commonly found on young maize, and to a less extent on 

 mature plants. The most beneficial insect is the Coccinellid that 

 was introduced from Hawaii, and in nearly all cases it has been found 

 on plants infested with Aphids and mealy-bugs. 



Early planting and clean cultivation considerably lessened the 

 injury to rice by Leptocorisa varicornis (rice bug). Little insect 

 damage occurred in the main rice crop. In the time-of-planting 

 experiments considerable injury was caused by a Pyrahd, which folded 

 the leaves together, thus preventing the growth of the plants. A small 

 amount of damage was caused by a stem-borer, probably Sesamia 

 [Nonagria) inferens. Until better remedial measures are found 

 it would be advisable to plant early maturing varieties either during 

 the end of August or the beginning of September and give the 

 adjoining fields clean cultivation. 



