250 



THE AGRICULTURAL NEWS. 



July 29, 1916. 



INSECT NOTES. 



AN INSECT DESTRUCTIVE TO STORED 



MAIZE. 



For nearly three-fourths of a century the larva of a 

 small moth (Batrachedra rileyi), commonly known as 

 the pink corn-worm, has been observed in the fields of 

 the Southern States, but according to Bulletin No. 3G8 

 issued by the Bureau of Entomology of the Ignited 

 States Department of Agriculture, it was not until 

 1914 that this species was recognized as a pest. 

 C'omplaints have been made of the serious damage 

 done by this insect to stored corn. It appears that the 

 injury is occasioned by the caterpillar, which devours 

 the interior of the grains. The caterpillar also feeds on 

 cotton. The great increase in the numbers of this 

 insect is said to be due probably to the destruction of 

 cotton bolls by ploughuig them under as a remedy 

 against the boll weevil. If the insect should be 

 introduced into the West Indies, it is probable that it 

 might occasion much trouble. The following is a sum- 

 mary of the facts in the Bulletin referred to above: — 



The so-called pink corn-worm is not a true worm, but 

 the caterpillar or larva of a minute moth known as Batra- 

 chedra rileyi. 



Attack on corn begins in the field and continues after 

 the corn has been stored. When the stored product is 

 husked, the infested ears show injury by accumulations of 

 webbing and frass, or excrementitious matter. A careful 

 inspection discloses the 'pink worm'. 



The eggs are deposited in the field where the tips of the 

 corn ears are more or less open, due to the attack of the corn 

 ear worm. After the latter has departed the pink corn-worm 

 continues the injury and by its work makes it easy for other 

 insects and vrater to enter tlie ears, which eventually are 

 ruined. 



From the cob or between the rows of grains the worm 

 penetrates the kernels at the tip or point of attachment, 

 works into the embryo or 'germ', which it destroys, then out- 

 ward to the crown. 



Unlike the Angoumois grain moth and the rice weevil, 

 which are usually to be found working in the same fields and 

 frequently in the same ears, this 'worm' does not confine 

 itself to the kernel, but attacks kernel, busk and cob alike. 



Also unlike most other graifi pests, it appears to be 

 confined among cereals to corn and sorghum, although it 

 attacks, but does not seriously injure, cotton bolls which are 

 more or less open, and some other plants. 



While thus tar it has proved most injurious in Missis- 

 sippi, it ranges from South Carolina westward tn Central 

 Te,\as, .southward to Tropical Texas, and northward to 

 Arkansas and Tennessee. 



])uring the years 19I1-1."> the pink corn-worm was 

 lejioitcd to have occasioned very considerable injury, and 

 nmch alarm was felt because of its abundance in the regions 

 mentioned. Previously, although known to attack corn, 

 it has never been considered a serious enemy of grain. 



Naturally it cannot be foretold when, if ever, such an 

 outbreak will occur. 



As a preventive of injur}-, corn should be left in the 

 field no longer than i.s absolutely necessary for drying it; the 

 huivks should then be removed as soon as possible, the poorest 



of the infested ears destroyed promptly or fed to swine or 

 poultry, and the best ears fumigated with carbon bisulphide. 



The bins or cribs should be kept scrupulously clean, and 

 should be fumigated before new material is stored in them. 



Co-operation among corn growers of as large a territory 

 as possible where the species occurs should be secured, that 

 future losses may be prevented. 



PROPAGATION RECIPES. 



Experiments in vegetative propagation of tropical fruits 

 have been continued at the Lamao Experiment Station in 

 the Philippines, as the result of which 'propagation recipes' 

 are given in the Philippine Agricultural Rei'iew relative 

 to species, amongst which the fallowing are of interest in 

 the West Indies : — 



Barbados cherry {Malpighiii i/labrn). Use petioled, 

 light gray to greenish, mature budwood: cut the buds 3'5 cm. 

 long; age of stock at the point of in.sertion of the bud 

 unimportant. 



Duhat {Eugenia jambolana). Use barely mature, 

 green or reddish, smooth, petioled budwood; cut the buds 

 4 to 4-5 cm. long; age of stock at the point of insertion of 

 the bud unimportant. 



Mangosteen (Garcinia mangostana). Like most other 

 tropical fruits the mangosteen is ^iropagated from seed. It 

 is of course self-evident that the propagation of seedle.ss 

 varieties or the extension of the mangosteen season cannot 

 be accomplished until the mangosteen can be propagated 

 asexually. However, the mangosteen is of such exceed- 

 ingly slow growth that it will probably never be chosen as 

 a stock until all other possibilities have been exhausted. 



Generally speaking, the requirements for successful 

 grafting or budding are about the same in related plants, 

 and in order to ascertain the ease with which Guttiferous 

 plants might be shield budded, a series of buds were 

 inserted on the Palo ilaria (Calophyllum inophyllum). These 

 buds, about one half of which were petioled, all made good 

 unions and sprouted without difficulty, which indicated that 

 related plants would likely be 'easy' subjects. A few plants 

 of the guta-gamba {Garcinia ivnulosa) were on hand and 

 these were also budded, and a dozen buds of this species 

 {Garcinia venulnsa) were also inserted in Calophyllum 

 inophyllum stock. All the buds took and made perfect 

 unions. Well-matured but green and smooth non-petioled 

 mangosteen budwood was then procured and buds inserted 

 both on Garcinia venulosa and Calophyllum inopltyllum. 

 ( Jood unions resulted in most instances. Four months after 

 the insertion of the buds, nearly all the buds of trarcinia 

 venulosa and .^3(1 per cent, of the mangosteen were still alive, 

 but had not sprouted and are gradually being callused over. 



EXPERIMENTS WITH STOCKS 



FOR CITRUS. 



Attention is being given in several quarters to the 

 interesting subject of the effect of the stock upon the scion. 

 The work that has been done in this connexion in California 

 with regard to citrus is of esjjecial interest in the West 

 Indies. For this rea.son is introducfd below a short account 

 of the results obtained, taken from Bulletin No. 267 of the 

 I'niversity of California publications (College of Agriculture). 

 The two stocks most commonly usi d i]> propagating citrus 

 trees in California are the sweet and the sour orange. In 

 addition to these, the pomeh) {Citrus tlecumana) has been 

 employed to some extent, as has also Citi-vs trifoliata. The 



