MEXICAN BEAN BEETLE IN THE SOUTHEAST. 



15 



destroyed, and serious injury in some instances was done to soy beans. 

 The following list of food plants comprises those observed to date, in 

 the order of their preference, on which both larva? and beetles can 

 subsist, as observed in the field. 



FOOD PLANTS OF THE MEXICAN BEAN BEETLE. 



Tepary bean (Phaseolus acutifolius) . 



Garden bean (Phaseolus vulgaris); including navy bean, pinto 



bean, kidney bean, pole bean, etc. 

 Lima bean (Phaseolus lunatus). 



Beggarweed (Meibomia tortuosa, M. canescens, M. viridiflora) . 

 Hyacinth bean (Dolichos lablab). 

 Cowpea and black-eyed pea (Vigna sinensis). 

 Soy bean (Glycine hispida). 

 Adsuki bean (Phaseolus angularis). 

 Alfalfa (Medicago saliva). 

 Sweet clover (Melilotus alba). 



Fig. 10. — Voluntary larval feeding on beggarweed {Meibomia sp.). 



There is a very great difference in choice between some of these 

 food plants. In some cases of light infestations, cowpeas and soy 

 beans may be uninjured. Also, early in the season, beetles and larvae 

 may starve in confinement on these plants, while later in the year 

 they will reproduce on them and may cause serious injury in the 

 field in cases of heavy infestations. 



In the late summer and fall, when bush bean foliage is scarce but 

 when pole Lima beans are large and green, the beetles are attracted 

 to the latter. This crop is examined closely in fall scouting work in 

 new territory. The list given is based on field observations. 



In the insectary the insect has been reared from egg to adult on 

 many varieties of bean — on Meibomia canescens (fig. 10), cowpea 

 (PI. VII, A, B), hyacinth bean, soy bean (PI. VIII, B), and adsuki 

 bean — and to the pupa stage on alfalfa, when ants destroyed the 

 pupse. The likelihood of the insect severely damaging plantings of 

 the adsuki bean, sweet clover, or alfalfa (PI IX, A) is very remote. 

 Beetles and larvse in confinement often starve in the presence of the 

 last two plants. When extremely numerous the beetles have been 



