Black bean (Phaseolus vulgaris L.) is a special type of beans, locally known as Akidi in Igbo. It is relished as a native delicacy and contributes significantly to the meals in most of the tropical communities. The black bean (Phaseolus vulgaris L.) is a nutrient-dense food that is high in proteins, minerals, vitamins, carbohydrates and fiber, all of which are needed for human health. Black beans have sufficient quantities of essential and non-essential amino acids to meet daily nutritional demands (Kotue et al., 2018). In addition to being an excellent source of protein, Fernandes et al. (2016) stated that black beans are rich in minerals, such as calcium, potassium, phosphorus, iron, copper, zinc and magnesium. Black beans contain soluble and insoluble dietary fibre that give them a great sense of satiety which is a desirable effect for weight loss (Ikezu et al., 2015). Regular consumption of black beans is linked to reduced cholesterol and coronary heart disease, beneficial effects against cancer, reduction of diabetes and obesity, high antioxidant capacity, anti-mutagenic and anti-proliferative activities (Nwadike et al., 2018).
       
Black beans have become the fastest growing market class of beans, which means people are eating a lot of black beans. However, the performance and yield of black beans is declining greatly to the extent that it is considered as one of the endangered species of crops (Ntukamazina et al., 2014). This was mainly due to poor agronomic practices where inadequate attention were paid to improve the production. Poor adoption of correct agronomic practises like inadequate spacing and poor seed rate leads to decline in egusi melon growth and yield (Ugwuoke et al., 2021). With improved agronomic practices like staking, climbing brown bean variety was reported to have produced up to 4 metric tonnes per hectare, while bush beans produced between 1 and 2 tonnes per hectare (Ntukamazina et al., 2014). Climbing beans grow vertically and thus need support by staking which help the plants to grow faster, healthier, reduce disease attack especially anthracnose, access enough light and produce higher yields. Staked beans have extra advantage of being harvested over a prolonged period compared to bush beans. Staking and weeding are essential agronomic practices in black beans that promote healthy crop growth and production. Weeds compete with crops for natural and applied resources, thereby causing reduction in quantity and quality of productivity (Rao and Chanuhan, 2015). Beans, being low-growing plants, struggle to compete with weeds for minerals, light and moisture especially during the early stage of crop growth. Some weeds are alternative hosts of pests and diseases. The weed seeds and shoots also reduce the quality and market value of harvested grains (MAAIF, 2019). Unfortunately, many bean farmers have not fully grasped the importance of staking and frequent weeding in black beans production. Hence, this study determined the effects of staking and weeding frequencies on the performance of black beans (Phaseolus vulgaris).

Experimental procedure
 
The study was conducted in 2023 and 2024 planting seasons at the Department of Agricultural Education demonstration farm, University of Nigeria, Nsukka located at 6.84°N, 7.37°E (Ugwuoke et al., 2020). The study adopted experimental research based on randomized complete block design (RCBD) which was replicated thrice. Land preparation was carried out according to the procedure described in Uguru (2011). Eighteen plots each measuring 1.5 m × 1 m with 0.5 m alley between were made and randomly assigned to six treatment groups with each replicating three times. The treatment groups were represented as T1 = staked and weeded every 2 weeks, T2 = staked and weeded every 4 weeks, T3 = not staked but weeded every 2 weeks, T4 = not staked but weeded every 4 weeks, T5 = staked and not weeded and T6 = not staked and not weeded (Control). Healthy and viable black bean seeds were purchased from the Department of Crop Science, University of Nigeria, Nsukka. The Black bean seeds were sown at a planting distance of 50 cm × 20 cm and two seeds per hole. Poultry manure was applied at 4t/ha and worked into the soil two weeks before planting to allow for decomposition, mineralization and nutrient release into the soil. Agronomic practices were done according to the recommendations of Duncan and Ewing, (2015).
 
Data analysis
 
The data collected from the 2023 and 2024 planting seasons were pooled and statistically analysed using mean and analysis of variance (ANOVA) at 0.05 level of significance while the separation of means for significant effects was carried out using least significant differences (LSD).

Effect of staking and weeding frequencies on the germination
 
Table 1 shows that the germination rate, germination percentage and germination index were recorded highest in black beans staked and weeded every 2 weeks (T1). The germination rate of T1 was found to be statistically significant (p<0.05) when compared to others (Table 1). The least germination rate, germination percentage and germination index were found in control (T6). The poor gemination parameters of black beans in control might be attributed to the harmful effects of weeds on crops. Some weeds exude chemical substances that have allelopathic effects on germination of some crops (Kadioôlu and Kanar, 2004). The germination percentage and seedling growth were found to be significantly affected by the extracts of Eleusine indica, Cyperus rotundus and Cynodon dactylon (Afrin et al., 2016). Early germinated black bean seedlings are usually strong, resistant to biotic and abiotic conditions that might attack the seedlings (Dugesar et al., 2025) thereby enhancing the growth and yield of black beans.


 
Effect of staking and weeding frequencies on the growth of black beans
 
Number of leaves/plant and vine length were best in black beans staked and weeded every 2 weeks (T1) which were statistically significant different (p<0.05) from other groups (Table 2). Number of leaves/plant and vine length were statistically lower in control (T6) when compared with other treatments. The results might be attributed to the staking which expose their leaves to sunlight for increased photosynthesis and faster growth. Plant height was found to be significantly higher in staked tomato than the un-staked group (Falodun and Bakare, 2023). Delay in weed removal was found to decrease growth and decline yield performance of soybeans (Daramola et al., 2020). The number of branches/plant of black beans were highest in the treatment group not staked and weeded every 4 weeks (T4) and least in control but not statistically significant (p>0.05) when compared to others. In another study, the dry bean height, number of leaves/plant and chlorophyll content were found to be lowest under no weeding control and increased as the weeding frequencies increase (Baker et al., 2021).


 
Effect of staking and weeding frequencies on the yields of black beans
 
Production of pods in black beans generally started at the 8WAP which coincides with 2 months after planting. Table 3 showed that the number of pods/plant, pod weight and number of seeds/pod were highest in black beans staked and weeded every 2 weeks and statistically significant different (p<0.05) from other treatments. The lowest number of pods/plant, pod weight and number of seeds/pod were obtained in control group (Table 3). The weight of pods decreased progressively from T1 to T6. Pradhan et al. (2021) reported that fruit yield and marketable fruits can be achieved by exposing the plant to adequate sunlight and ventilation following proper staking. Staking increased fruit diameter, fruit length and marketable size of tomato when compared to the control (Lamptey and Koomson, 2021). The increase in yield parameters in black beans staked and weeded every 2 weeks could also be attributed to the constant weeding practice. Tomatos weeded every 2 weeks were found to produce more fruits yield and better shelf-life than other treatments (Babatola and Olaniyi, 2007). Poor weed control in cowpea was detrimental to the yield resulting to a loss ranging from 25%-76% (Manibharathi et al., 2024).



Effect of staking and weeding frequencies on harvest duration of black beans
 
Table 4 showed that the duration of black beans harvest decreased progressively from T1-T6. The duration of harvest was highest in black beans staked and weeded every 2 weeks which was followed by the black beans staked and weeded every 4 weeks (Table 4). The shortest harvest duration was recorded in control. The shortest harvest period in the control might be the smothering effect of weed that overshadowed the black bean plants, particularly as they were not staked. Black beans being creeping plant is susceptible to weed attack. Iderawumi and Friday, (2018) reported a total suppression and early death of maize plant when weeding was delayed. Weeding every 2 weeks was discovered to reduce the incidence of pest associated with weed infestation in crops which progressively increased as the weeding was delayed and became disastrous in control where weeding was not done (Iledun and Durojaye, 2020). Delayed weeding in rice farm was found to have irreversible effects on growth pattern and death of plants before maturity (Kolo et al. 2021).

Black bean is a weak stemmed plant that cannot stand erect. It creeps on soil when not staked. Weeds attack black beans by covering and smothering the plant, inhabit pests and diseases that attack black beans, exude chemical substances that affect the growth and production and early death of the plant. Staking and weeding every two weeks increased the plant height, number of leaves and branches, number of pods, pods weight, number of seeds/pod and harvest duration.

All authors declare that they have no conflict of interest.