The assessment revealed that there is a lack of suitable production systems, innovative processing, and value-adding techniques that promote the utilization of African leafy vegetables. It was also observed that African leafy vegetables are food for the poor among the youth and urban folks, while, among the affluent, they are highly regarded as being nutritious. Navy bean production was hampered by many constraints among which are lack of diversity in terms of buyers/off-takers, non-payment for produce in hard currency, delayed payment by contractor, low grain producer price and inflation eroding the value of the produce . The other major challenging constraints among both male and female farmers were lack of transport to ferry produce, non-transparent grading, expensive packaging material and breach of contract by contractor. About 45 and 13% of the farmers across all the locations desired high grain yield and disease tolerance of the Zimbabwe White Bean cultivar, respectively (Fig. 2). However, more than 15% of the farmers indicated they did not like any attribute of the Zimbabwe White Bean and Teabus cultivars, but they were the only available cultivars that were offered by the contractor/canning company. Even though Caledon was not widely grown, 2% of the farmers who cultivated the cultivar liked the high grain yield potential of the cultivar.
When cowpea seeds were planted in a soil profile with enough water to allow germination and emergence, they survived for 43 days under very hot dry summer conditions with no rain, but were badly stunted. This endurance of vegetative-stage drought was due to increased leaf water retention in cowpea than pearl millet . Cowpeas exhibit little changes in leaf water and osmotic potential when exposed to drought . Cowpeas also have stomata that are very sensitive to soil drying, partially closing before any changes in leaf water potential are detected . When cowpea plants are subjected to drought in field conditions, their leaves do not dry out but are arranged vertically following the sun in a way that limits the exposure of solar radiation .
Production Constraints And Improvement Strategies Of Cowpea Vigna Unguiculata L Walp Genotypes For Drought Tolerance
It recognizes that partial automation is significantly less expensive than full automation. Jidoka also emphasizes automatic stoppage of equipment when defects are detected.In some cases, the constraint cannot be broken without significant capital investment. Enables smoother startups, since a simplified and standardized changeover process improves quality and consistency. Optimizes constraint and non-constraint running speeds to maximize throughput and reduce the frequency of minor stops. Synchronizes material usage at the constraint with material usage in the upstream process by controlling when new materials are released into the process. One of the most powerful aspects of the Theory of Constraints is its laser-like focus on improving the constraint.
Ethiopia, Central Africa, Central and Southern Africa, and West Africa are considered as possible centers of origin . Apart from nutrients, cowpea has dietary fibre, antioxidants and polyunsaturated fatty acids , and polyphenols . Information on the production constraints and farmer’s views, perceptions, and variety preferences in Zimbabwe are not yet fully documented. However, Mujaju and Mazvimavi assessed seed security in the four most vulnerable districts in Zimbabwe. These four districts were Mudzi, Binga, Buhera, and Mwenezi, which are always prone to droughts.
This approach ensures smoothed demand at the aggregation point, requiring proportionally less inventory. The distribution centers holding the aggregated stock are able to ship goods downstream to the next link in the supply chain much more quickly than a make-to-order manufacturer can. The TOC distribution solution is effective when used to address a single link in the supply chain and more so across the entire system, even if that system comprises many different companies. The purpose of the TOC distribution solution is to establish a competitive advantage based on extraordinary availability by reducing the damages caused when the flow of goods is interrupted by shortages and surpluses. However, for many organizations and non-profit businesses, making money is a necessary condition for pursuing the goal. Whether it is the goal or a necessary condition, understanding how to make sound financial decisions based on throughput, inventory, and operating expense is a critical requirement. The theory of constraints is an overall management philosophy, introduced by Eliyahu M. Goldratt in his 1984 book titled The Goal, that is geared to help organizations continually achieve their goals.
There is often uncertainty about the expected timing of water breakthrough, and this should be accounted for in the range of production profiles developed. An increase in water and/or gas production can lead to producers being shut-in due to lack of water handling or gas compression capacity. Well production prioritization then needs to be considered until constraints can be lifted. Advanced Planning and Scheduling Softwares have become a must for modern-day manufacturing operations as customer demand for increased product assortment, fast delivery, and downward cost pressures become prevalent. These systems help planners save time while providing greater agility in updating ever-changing priorities, production schedules, and inventory plans.
APS Systems can be quickly integrated with an ERP/MRP software to fill the gaps where these systems lack planning and scheduling flexibility, accuracy, and efficiency. In addition, this software will quickly identify production bottlenecks before problems occur and allow you to adjust production in advance. An integrated APS software can greatly reduce the response and remediation time required to deal with constraints and bottlenecks in production. Your company’s performance will be optimized so that you can deliver items on time and maximize your profits. Resolve Bottlenecks – Once you have identified the long-term bottlenecks that are negatively impacting the production operations, you can find the best solution to resolve it.
The questionnaire had five components namely, demographic information, navy bean cropping systems , farmers’ trait preferences of navy bean cultivars, navy bean production constraints and strategies used to mitigate some of these constraints. Mixed cropping is the production of two or more crops simultaneously on the same piece of land without row arrangements, whereas sole cropping is the growing of one crop cultivar in pure stands alone.
Determine the Type of Bottleneck – When the bottleneck constraint is identified, it is declared a long-term or a short-term bottleneck. Short-term bottlenecks are usually isolated incidents that are resolved within a period of time.
- This is because the resistance of cowpeas to vegetative-stage drought breaks down and the plants die.
- On the other hand, insect pests , diseases , drought and heat stress affect the canning quality of the grain resulting in the rejection of the commodity by food processors.
- In other words, if the buffer is 5 days, the order is released 5 days before it is due at the constraint.
- In Gudyanga and Nenhowe villages, navy bean was ranked second by 8.0 and 14.8% of the male respondents, respectively, while in Maunganidze village among men, it occupied the third (8.0%) place after sorghum and wheat, which were ranked equally (16.4%).
No matter how well your manufacturing operations are running, you can usually identify bottlenecks that are reducing the overall production capacity. In supply chain management, bottlenecks can present repetitive obstacles in production for most manufacturing and production facilities and will hinder the optimization of output and profitability. While originally focused on manufacturing and logistics, TOC has expanded into sales management and marketing. For effective sales management one can apply Drum Buffer Rope to the sales process similar to the way it is applied to operations . This technique is appropriate when your constraint is in the sales process itself, or if you just want an effective sales management technique which includes the topics of funnel management and conversion rates.
Applying Lean Tools To elevate The Constraint
Buffers in DBR provide the additional lead time beyond the required set up and process times, for materials in the product flow. Since these buffers have time as their unit of measure, rather than quantity of material, this makes the priority system operate strictly based on the time an order is expected to be at the drum. Based on this buffer status, work orders can be color coded into Red, Yellow and Green. The red orders have the highest priority and must be worked on first, since they have penetrated most into their buffers followed by yellow and green.
Drought stress and heat stress were the most important constraints because farmers are not able to grow navy beans during the main cropping season due to erratic rainfall totals coupled with high temperatures (more than 32 °C) . Load shedding in winter was also an important constraint because it affected the frequency of irrigation cycles resulting in the crop experiencing prolonged periods of moisture stress. Farmers were forced to irrigate at night when electricity was available, a strategy which was often a challenge to women farmers due to household responsibilities/duties. There was a fair level of consistency in trait preference rankings by both men and women probably because all the farmers experienced the same production and marketing constraints.
Sales agreements are more common for gas fields, and in these cases, the production forecast is likely to depend heavily on customer requirements. The sales agreement will usually call for a long-term plateau rate but, within this, ACQ and DCQ may vary.
Definition Of ’constraint’
Generally, navy bean was cultivated in small fields because most contracting companies availed seed which was enough to cover an area of 0.25 ha per farmer. This was used as a risk management strategy against biotic, abiotic and socio-economic constraints coupled with the unavailability of seed.
Definition Of ’production’
Farmers revealed that most of the navy bean contractors were paying an average of USD800 per tonne, a price which they feel was low compared to what middlemen were paying for the sugar bean grain market class. This could be due to lack of diversity in terms of buyers/off-takers in the navy bean market. It was mainly the canning companies who were contracting farmers to produce navy bean grain and subsequently purchasing the grain from them such that there was no competition from other players/off-takers/middlemen.
While CRT represents the undesirable effects of the current situation, the FRT , NBR help people plan and understand the possible results of their actions. The PRT and TRT are designed to build collective buy in and aid in the Implementation phase.
Since policy constraints often stem from long-established and widely accepted policies, they can be particularly difficult to identify and even harder to overcome. It is typically much easier for an external party to identify policy constraints, since an external party is less likely to take existing policies for granted. There are also differing opinions on whether a system can have more than one constraint. The conventional wisdom is that most systems have one constraint, and occasionally a system may have two or three constraints.
Early maturing cultivars can also be grown during the main short rainfall season in summer, and in winter, they escape heat stress and bean rust disease by maturing before temperatures begin to rise in July. Asfaw et al. , Balcha and Tigabu , and Assefa et al. reported that dry bean farmers considered earliness as an important selection criterion in drought prone areas. Farmers preferred cultivars that are tolerant to pod shattering to reduce the amount of time and labour spent in picking the small seeded grains from the ground. This is corroborated by Asfaw et al. who reported that farmers in Ethiopia preferred dry bean genotypes that were tolerant to pod shattering. Tolerance to diseases was one of the most preferred traits due to high costs of fungicides and the need to reduce the amount of labour and time spent on processing diseased grain, which was often done by women. Farming enterprises were business oriented evidenced by the type of crops grown which ranged from horticultural crops, cereals, and others. The diversification of crops protected farmers from natural hazards such as drought, guaranteeing food, nutrition and income security at farm level.