Effects of four host plants, tobacco, Chinese cabbage, cowpea and sweet potato, on larval and pupal development and survival, and longevity and fecundity of adults of Spodoptera litura (F) (Lepidoptera: Noctuidae), were studied under laboratory conditions (26 degrees C, 60-80% RH), as was the utilization of the four host plants and adaptation on tobacco. All of the biological parameters include...

Sweet potato (Solanum tuberosum), a staple tuber crop in parts of the Sudan and Guinea savanna zone of Nigeria is known for its resistance to drought, vigorous early growth and low input requirements. Increase in population which has resulted to land shortages has led to reduction in traditional methods of maintaining soil fertility. Technologies based on combinations of organic and inorganic s...

The sweet potato (Ipomoea batatas L.) is a crop of great importance in developing countries, as a food staple, for animal feed, and potentially for biofuel. Development of cultivars adapted to specific regions within these countries would be useful. To start a breeding program, the first step is the establishment of a germplasm bank. We initiated a sweet potato germplasm bank with accessions co...

The effect of dietary fibre and starch content on digestibility, microfaunal population and caecal function was investigated in a subterranean mole-rat, Heterocephalus glaber (Rodentia). Mole-rats were fed on a diet of either sweet potato (neutral-detergent fibre (NDF) 65 g/kg dry matter (DM), starch 638 g/kg DM) or carrot (NDF 157 g/kg DM, starch 258.7 g/kg DM) for 4 weeks. Daily intake and fa...

The effect of cooking methods on some proximate properties of sweet potato (Ipomoea batatas L) was investigated. With the initial properties of the fresh sweet potatoes (sample A) determined, 600g each of samples B, C and D were boiled peeled, boiled unpeeled and roasted unpeeled respectively. The properties determined for the samples are moisture content, ash, fibre, protein, fat, carbohydrate...

Two serologically unrelated sweet potato viruses causing symptoms of vein clearing in the indicator plant Ipomoea setosa were isolated and their genomes have been sequenced. They are associated with symptomless infections in sweet potato but distinct vein-clearing symptoms and higher virus titres were observed when these viruses co-infected with sweet potato chlorotic stunt virus (SPCSV), a vir...

This paper summarizes a series of field experiments that investigated the effects of organic and inorganic nutrients on sweet potato tuber yield in the humid lowlands of Papua New Guinea. In the first experiment, plots were planted with Piper aduncum, Gliricidia sepium and Imperata cylindrica, which were slashed after one year, whereafter sweet potato was planted. Sweet potato yield was lowest ...

The effects of frying unripe plantain and sweet potato (separately) in soyabean oil on the properties of the oil were investigated. Also, the effect of the degradation of the oil on biodiesel yield obtained from the oil was considered. Physico-chemical properties of soyabean oil (acid value, saponification value, viscosity, density, colour) were measured daily after being used for frying for da...

Nematode population densities and yield of sweet potato and onion as affected by nematicides and time of application were determined in a 3-year test. Population densities of Meloidogyne incognita race 1 in untreated plots of sweet potato increased each year, but Helicotylenchus dihystera and Criconemella ornata did not. Ethoprop (6.8 kg a.i./ha) incorporated broadcast in the top 15-cm soil lay...

Sweet potato (Ipomoea batatas) is an important subsistence and famine reserve crop grown in developing countries where Sweet potato chlorotic stunt virus (SPCSV; Closteroviridae), a single-stranded RNA (ssRNA) crinivirus, synergizes unrelated viruses in co-infected sweet potato plants. The most severe disease and yield losses are caused by co-infection with SPCSV and a potyvirus, Sweet potato f...