MSUIR Collection:

Variety and planting date effects on the incidence of bollworms and insect sucking pests of cotton (Gossypium hirsutum L.)

Karavina, Charles — Sun, 01 Jan 2012 00:00:00 GMT

Title: Variety and planting date effects on the incidence of bollworms and insect sucking pests of cotton (Gossypium hirsutum L.) Authors: Karavina, Charles; Mandumbu, Ronald; Parwada, Cosmas; Mungunyana, T. Abstract: Cotton is a major foreign currency earner in Zimbabwe. It is attacked by many insect pests which limit its productivity. A trial carried out at the Cotton Research Institute investigated the effects of planting date and cotton variety on the incidence of bollworms and insect sucking pests of cotton. Three varieties SZ 9314, CRI MS1 and CRI MS2 were planted on three different dates (20 October, 17 November and 15 December), representing early, mid-season and late planting times. Scouting for pests commenced from the fifth week after emergence to 10% boll split. Both planting date (p = 0.027) and cotton variety (p = 0.012) had significant effects on pest incidence. Early planted cotton had lower aphids, jassids and red bollworm population than later-planted cotton. This was due to the higher natural enemies’ population and the effects of the “closed season” in the early crop. CRI MS2 hosted significantly lower populations of aphids, jassids and red bollworms compared to the other varieties. There was interaction between planting date and variety, with early-planted CRI MS2 hosting the lowest populations of aphids and red bollworms. The study concluded that early planting resulted in lower incidence of insect sucking pests and recommended the early planting of CRI MS2.

Effect of ridge height and planting orientation on Ipomea batatas (sweet potato) production

Parwada, Cosmas — Sat, 01 Jan 2011 00:00:00 GMT

Title: Effect of ridge height and planting orientation on Ipomea batatas (sweet potato) production Authors: Parwada, Cosmas; Gadzirayi, Christopher T.; Sithole, A. B. Abstract: Ipomea batatas (sweet potato) yield vary widely among farmers due to improper ridging and planting orientation. This study was to establish the proper ridging and planting orientation, so as to enhance constant reliable yields among sweet potato producing farmers. The objectives of the study were to compare vine length and to determine root yield, central root diameter and root length among different ridge heights and planting orientations. A 3 x 3 factorial in a completely randomised block design with 3 replications was used. Ridge height had levels; 30, 40 and 50 cm while planting angle had levels; horizontal 180°, inclined 45° and vertical 90°. Vine length was measured at 3, 6, 9 and 12 weeks after planting and root yield, root diameter and root length were measured at harvesting. Data was analysed using M STAT C for variance between treatment means. The results showed interaction effect (p = 0.05) of ridge height and planting angle on the vine length, root diameter, length and yield. Lower ridges produced longer vines than higher ridges. Decreasing inclination of cuttings also increases vine length. Root diameter decreases with increasing ridge height while root length increased as ridge height increased. Medium ridge height (40 cm) with inclined planting angle may be recommended for higher root yields and horizontal planting angle on low ridges can be used to produce rounded swollen roots.

Effect of soil fertility amendment, planting density and growing season on Chenopodium quinoa Willd (Quinoa) in Zimbabwe

Parwada, Cosmas — Wed, 01 Jan 2020 00:00:00 GMT

Title: Effect of soil fertility amendment, planting density and growing season on Chenopodium quinoa Willd (Quinoa) in Zimbabwe Authors: Parwada, Cosmas; Mandumbu, Ronald; Tibugari, Handsen; Badze, Doreen; Mhungu, Somerset Abstract: Chenopodium quinoa Willd (quinoa) is a crop that originated from the Andes and has been recently introduced in Zimbabwe so the agronomic performance is unknown yet. A 3-year field experiment was carried out at the Women’s University in Africa research farm, Marondera, Zimbabwe. The research evaluated the response of quinoa to different cattle manure application rates, plant population ha−1 and growing seasons. A 3 × 3 × 2 factorial in a completely randomized block design with three replicates was used in the experiment. Cherry Vanilla Quinoa variety was established under three cattle manure application rates (0, 9 and 18 t ha−1), three planting densities (29629, 55555 and 80 000 plants ha−1) and two growing seasons per year (summer and winter). Analysis of variance was done to compare the effects of the treatments on quinoa growth parameters. There was significant (P < 0.05) interaction on cattle manure application rates × plant population ha−1 × growing season in all the measured response variables. The vegetative phase was higher on soil fertility amended than unamended plots in summer than winter regardless of the planting density. Highest grain yield (2.5 t ha−1) and thousand grain weight (T.G.W) (2.5 g) were recorded in winter at 9 t ha−1 + 55,555 plants ha−1 while lowest T.G.W (0.2 g) and grain yield (0.1 t ha−1) were noted in 18 t ha−1 + 80,000 plants ha−1 in summer. Quinoa can be grown in winter or summer with 9 t ha−1 + 55555 plants ha−1 for grain or biomass, respectively.

Macadamia nuts (Macadamia integrifolia) value chain and technical efficiency among the small-scale farmers in Zimbabwe

Bandason, Wellington — Sat, 01 Jan 2022 00:00:00 GMT

Title: Macadamia nuts (Macadamia integrifolia) value chain and technical efficiency among the small-scale farmers in Zimbabwe Authors: Bandason, Wellington; Parwada, Cosmas; Mushunje, Abbyssinia Abstract: Agriculture value chains are an indispensable tool for stakeholder collaboration, improving market access, foreign currency generation and increase in macadamia nut production in most developing countries. In Zimbabwe macadamia nut is a relatively new crop that has potential to alleviate poverty and enhance livelihoods. Zimbabwe’s macadamia nut industry is still at its infancy and remains an under-researched area. Despite this, the technical efficiency of macadamia nuts production systems as proxied by production levels among small-scale farmers in the country is least understood. This study analyses the existing value chains by scrutinizing every step required in the production and marketing of macadamia nuts focusing on technical efficiency of value chain nodes. Macadamia nut value chain in Zimbabwe is predominantly an emergency value chain system that does not embrace the modular value chain model and associated networks to enhance technical efficiency and overall welfare. The value chain system is characterised by imperfect market conditions with limited knowledge of exact specifications, attributes and price of macadamia nuts. The existing value chain models for macadamia nut need to be re-aligned to accommodate all stakeholders, hence widening resource and knowledge sharing platforms. There is a need for the Zimbabwe macadamia nut value chain to shift towards captive networks which embrace and scale out practices such as out-grower contractual arrangements. There is potential to design macadamia nut value chain models in Zimbabwe to increase the technical efficiency of the industry.