Plant tissue culture aided with biotechnological approaches results to sustainable agricultural development capable of providing solutions to issues of food security. Bananas and plantains, both belonging to Musaceae, constitute one of the major staple foods and major fruit crops for many people in the world. Only a few out of over 300 kinds of banana have agricultural and economic importance. It is important to improve the productivity of banana as various abiotic and biotic constraints affect its production. There is increasing demand for tissue cultured banana plants due to its uses in producing disease-free planting materials, genetic transformation and crop improvement. Immature male and female flowers have high embryogenic potentials. Conventional method of banana cultivation using suckers is not sustainable and contamination is a major challenge in in-vitro micropropagation of banana. Therefore, aim of this review is to elucidate the advances made in tissue culture technology recently. The paper also highlights the aseptic conditions that can be adopted in the production of disease-free planting materials and successful improvement of the banana crop.

The production of pearl millet (Pennisetum glaucum (L.) R.Br.) is important in Namibia, in sub-Saharan Africa, owing to the prevailing low precipitation conditions. Most fields supporting crop production in northern Namibia are located in a network of seasonal wetlands. The aim of the present study was to evaluate the effects of ridging and fertilizer application on the yield and the growth of pearl millet in the seasonal wetlands under different rainfall conditions. The study was conducted for two years (2017–2018) in the experimental fields in northern Namibia, and yield, yield components, and growth parameters were evaluated in relation to the application of different fertilizers (manure and mineral) with and without ridge-furrows. Manure fertilizer application presented the highest yield in 2018, whereas mineral fertilizer application showed the highest yield in 2017. The proportion of rainfall was the highest during the mid-growth period in 2017, and the reproductive stage in 2018. Thus, pearl millet plants under manure fertilization overcame damage resulting from waterlogging stress during the seed setting stage by improving the soil and plant nutrient conditions. In contrast, the plants under mineral fertilization were more tolerant to large amounts of rain during the mid-growth period. In this study, yield was mainly determined by total dry weight, and it was closely related to panicle density in both years. Therefore, we concluded that fertilizer application, including additional fertilizer based on the growth diagnostic, could be important for improving crop production in seasonal wetlands.

Bambara groundnut (Vigna subterranea (L) Verdc.) is an orphan, underutilised and less exploited crop in Africa and beyond, yet it is an essential traditional crop for subsistence farmers in sub-Saharan Africa. Currently, in Namibia, neither a pre-breeding nor a breeding programme exists for Bambara groundnut. Twenty-five Bambara groundnut accessions acquired locally and outside Namibia were characterised for descriptor state, including possible character diversity on the quantitative descriptors. Square lattice design with three replications was used. Data were analysed using analysis of variance (ANOVA), Pearson correlation moment, Principal Component Analysis (PCA), and cluster analysis. ANOVA indicated significant differences (P < 0.05) among accessions for most of the characters measured, and highly significant differences (P < 0.01) for the number of pods per plant, pod yield, seed yield, plant height, and dry biomass. The dendrogram sub-criterion indicated three clusters, confirming the results of the PCA, which grouped accessions with common descriptors in the same quadrants. PCA biplot showed that the first two components explained 59.55% of the variation. Overall results suggest that the Bambara groundnut accessions evaluated in this study showed high variability, thus can be used as a source of pre-breeding materials to initiate a national breeding programme.

In semi-arid regions, climate change has affected crop growing season length and sowing time, potentially causing low yield of the rainfed staple crop pearl millet (Pennisetum glaucum L.) and food insecurity among smallholder farmers. In this study, we used 1994–2023 rainfall data from Namibia’s semi-arid North-Central Region (NCR), receiving November–April summer rainfall, to analyze rainfall patterns and trends and their implications on the growing season to propose climate adaptation options for the region. The results revealed high annual and monthly rainfall variabilities, with nonsignificant negative trends for November–February rainfalls, implying a shortening growing season. Furthermore, we determined the effects of sowing date on grain yields of the early-maturing Okashana-2 and local landrace Kantana pearl millet varieties and the optimal sowing window for the region, using data from a two-year split-plot field experiment conducted at the University of Namibia—Ogongo Campus, NCR, during the rainy season. Cubic polynomial regression models were applied to grain-yield data sets to predict grain production for any sowing date between January and March. Both varieties produced the highest grain yields under January sowings, with Kantana exhibiting a higher yield potential than Okashana-2. Kantana, sown by 14 January, had a yield advantage of up to 36% over Okashana-2, but its yield gradually reduced with delays in sowing. Okashana-2 exhibited higher yield stability across January sowings, surpassing Kantana’s yields by up to 9.4% following the 14 January sowing. We determined the pearl millet optimal sowing window for the NCR to be from 1–7 and 1–21 January for Kantana and Okashana-2, respectively. These results suggest that co-cultivation of early and late pearl millet varieties and growing early-maturing varieties under delayed seasons could stabilize grain production in northern Namibia and enhance farmers’ climate adaptation. Policymakers for semi-arid agricultural regions could utilize this information to adjust local seed systems and extension strategies.

Crop production in small-scale farming communities in semi-arid Central Namibia faces significant challenges due to the high costs associated with irrigation and fertilizers. This study evaluated the impact of different irrigation levels (full and reduced) and six types of soil amendments—biochar, compost, zeolite, NPK, Be-Grow Boost (L) hydrogel, hoof and horn combined with a bone meal (HHB meal), and control on the economic benefits of cabbage production and assessed their feasibility. In the first experiment, irrigation was implemented at 79.6 m³ (100% of the water requirement) for four days a week, classified as full irrigation, and at 39.6 m³ (50% of the water requirement) for two days a week, termed reduced irrigation. Among the fully irrigated treatments, Be-Grow Boost (L) hydrogel, zeolite, and NPK demonstrated the highest Benefit-Cost Ratios (BCRs) at 3.81, 3.67, and 3.65, respectively. In the second experiment, irrigation schedules were adjusted to five and four days per week, using a total of 136.0 m³ (170% of the water requirement) and 124.8 m³ (150% of the water requirement) of water. The compost, HHB meal, and NPK application rates were also modified. The fully irrigated Be-Grow Boost (L) hydrogel, NPK, and reduced irrigation with HHB meal achieved the highest and comparable yields of marketable cabbage heads per hectare, with BCRs of 3.43, 3.24, and 3.29, respectively. In conclusion, utilizing fully irrigated Be-Grow Boost (L) hydrogel, NPK, and reduced irrigation with HHB meal could be effective practices for sustainable crop production in the semi-arid, sandy soil conditions typical of Central Namibia. Moreover, local biochar production could enhance sustainability by reducing overall production costs.

In semi‐arid Central Namibia, poor sandy soils limit sustainable crop production. We assessed cabbage performance in two split‐plot field experiments. In Experiment 1, treatments comprised two irrigation levels: full irrigation (watered 3 days a week) and reduced irrigation (watered 2 days a week) as the main plot factor and six soil amendments (biochar; compost; zeolite; nitrogen, phosphorus potassium [NPK]; Be‐Grow boost [L] hydrogel; and hoof and horn + bone [HHB] meal) as subplot factors in three replications. Full irrigation produced a significantly higher yield (21.1 t ha⁻¹), head weight (0.958 kg) and larger head girths (42.1 cm). Biochar produced the highest marketable heads (24,884 heads ha⁻¹), water use efficiency (76.0 kg ha⁻¹ mm⁻¹) and the largest head girths (42.7 cm). In Experiment 2, water was applied 5 and 4 days a week for full and reduced irrigation; the application rates of compost, HHB meal, Be‐Grow boost (L) hydrogel and NPK were modified. The interaction of Be‐Grow boost (L) hydrogel, NPK and biochar with full irrigation and HHB meal with reduced irrigation produced more marketable heads (28,935, 28,009, 27,546 and 28,703 heads ha⁻¹, respectively). Therefore, full irrigation with these amendments could be used for resilient cabbage production in Central Namibia.