Using agronomic tools to improve pineapple quality and its uniformity in Benin

Keywords: Ananas comosus; Benin; cultural practices; fruit quality; hapas; heterogeneity; planting material; slips; suckers; supply chain; variation in quality; variation within crop; vigour. Poor average quality and uniformity in quality have become major issues in agri-food chains. This is also the case in the pineapple sector in Benin where less than 2% of the fresh pineapple is exported to international markets. The average quality of pineapple delivered to other markets, local and regional, is poor. The present thesis studied the improvement options in the pineapple sector which will help pineapple producers to produce higher pineapple quality for different markets, including international ones. This thesis aimed at (1) understanding how fresh pineapple supply chains are organised in Benin and identifying the bottlenecks for delivering the right pineapple to the right market; (2) increasing our knowledge on the agronomic tools used by pineapple producers to produce pineapple fruits; (3) understanding how agronomic factors affect pineapple quality and harvesting time, and (4) proposing and discussing the trade-offs between cultural practices. Research included analysis of supply chains and cropping systems and field experimentation. To understand how fresh pineapple supply chains are organised, 54 semi-structured interviews were held with key informants and 173 structured interviews with actor groups. Results indicated six main actor groups in the fresh pineapple chains: primary producers, exporters, wholesalers (those selling at local markets and those selling at regional markets), processors, retailers, and middlemen. Two pineapple cultivars were grown: Sugarloaf and Smooth Cayenne, with Sugarloaf being dominant in local and regional markets and Smooth Cayenne in European markets. The main constraints hampering the effectivity of the chains were: the non-controlled conditions under which the pineapple was transported from one actor group to another, the lack of appropriate storage facilities at wholesaler’s and processor’s levels, the unavailability of boxes for export and the non-concordance between actor groups in which quality attributes and criteria they valued most. In addition, most respondents interviewed affirmed that the pineapple quality was highly heterogeneous, emphasising the need to understand how pineapple is grown in Benin and what the constraints for producing high pineapple quality are. To find out the agronomic tools in use by pineapple producers in Benin, interviews were held with 100 producers in the pineapple production areas. Pineapple production practices proved diverse for both cultivars in planting density, flowering induction practice and fertiliser application. The production systems of the two pineapple cultivars differed in planting material used (slips in cv. Sugarloaf; hapas plus suckers in cv. Smooth Cayenne); the use of K2SO4 (not commonly used in cv. Sugarloaf and commonly used in cv. Smooth Cayenne); the number of fertiliser applications (lower in cv. Sugarloaf than in cv. Smooth Cayenne) and in the maturity synchronisation practice by means of Ethephon (not commonly used in cv. Sugarloaf and commonly used in cv. Smooth Cayenne). Constraints for high quality production were the unavailability of planting material, unavailability and high costs of fertilisers and the heterogeneity in planting material weight. To understand how agronomic factors affect pineapple quality and harvesting time, four on-farm experiments were conducted in commercial pineapple fields. Results first indicated that the heterogeneity in fruit weight was a consequence of the heterogeneity in plant vigour at artificial flowering induction time. The plant vigour at flowering induction was mainly related with the infructescence weight and less or not with crown weight. Second, results indicated that artificial flowering induction gave fruits with lower infructescence weight and heavier crown than natural flowering induction. Artificial maturity induction reduced the total soluble solids (TSS) concentration in the fruits. Finally, results showed that the reason why a high proportion of fruits in cv. Sugarloaf was not exportable to Europe was the high value in the ratio crown: infructescence height (above 1.5); in cv. Smooth Cayenne, reasons were a ratio crown: infructescence height as well as a TSS below 12 ºBrix. To come up with improvement options for high pineapple quality production with low heterogeneity in quality, the possibility of pruning slips on selective plants as means to improve uniformity in fruit quality was evaluated through two on-farm experiments on commercial fields with cv. Sugarloaf. Results revealed that pruning of slips did not significantly improve average fruit quality attributes and was not successful in achieving more uniform fruit quality at harvesting time. Through one experiment per pineapple cultivar, we investigated how fruit quality and its variation were affected by weight (in both pineapple cultivars) and type (in cv. Smooth Cayenne only) of planting material. Results showed that fruits from heavy planting material had heavier infructescence and fruit weights, longer infructescence height, but shorter crown height and smaller ratio crown: infructescence height than those from light planting material. In cv. Sugarloaf fruits from heavy planting material had higher variation in crown weight and lower variation in infructescence height than fruits from light and mixed (light plus heavy) planting materials. In cv. Smooth Cayenne, fruits from heavy planting material had a lower variation in fruit height than fruits from other classes of planting material. The type of planting material (in cv. Smooth Cayenne) had no effect on the average fruit quality attributes except on the crown height where fruits from hapas had shorter crowns than those from suckers. The type of planting material had in overall no significant effect on the variation in the fruit quality attributes. The present study is a step towards the improvement of the whole pineapple sector in Benin. It identified constraints for high pineapple quality production but also tested and proposed improvement options for high pineapple quality production. </p

Influence of weight and type of planting material on fruit quality and its heterogeneity in pineapple [Ananas comosus (L.) Merrill]

Cultural practices can affect the quality of pineapple fruits and its variation. The objectives of this study were to investigate (a) effects of weight class and type of planting material on fruit quality, heterogeneity in quality and proportion and yield of fruits meeting European export standards, and (b) the improvement in quality, proportion and yield of fruits meeting export standards when flowering was induced at optimum time. Experiments were conducted in Benin with cvs Sugarloaf (a Perola type) and Smooth Cayenne. In cv. Sugarloaf, experimental factors were weight class of planting material (light, mixed, heavy) and time of flowering induction (farmers', optimum) (Experiment 1). In cv. Smooth Cayenne an additional experimental factor was the type of planting material (hapas, ground suckers, a mixture of the two) (Experiment 2). Fruits from heavy planting material had higher infructescence and fruit weights, longer infructescences, shorter crowns, and smaller crown: infructescence length than fruits from light planting material. The type of planting material in Experiment 2 did not significantly affect fruit quality except crown length: fruits from hapas had shorter crowns than those from ground suckers. Crops from heavy planting material had a higher proportion and yield of fruits meeting export standards than those from other weight classes in Experiment 1 only; also the type of planting material in Experiment 2 did not affect these variates. Heterogeneity in fruit quality was usually not reduced by selecting only light or heavy planting material instead of mixing weights; incidentally the coefficient of variation was significantly reduced in fruits from heavy slips only. Heterogeneity was also not reduced by not mixing hapas and ground suckers. Flowering induction at optimum time increased the proportion and yield of fruits meeting export standards in fruits from light and mixed slip weights and in those from the mixture of heavy hapas plus ground suckers

Heterogeneity in pineapple fruit quality results from plant heterogeneity at flower induction

Heterogeneity in fruit quality constitutes a major constraint in agri-food chains. In this paper the sources of the heterogeneity in pineapple in the field were studied in four experiments in commercial pineapple fields. The aims were to determine (a) whether differences in pineapple fruit quality among individual fruits are associated with differences in vigor of the individual plants within the crop at the time of artificial flower induction; and (b) whether the side shoots produced by the plant during the generative phase account for the fruit quality heterogeneity. Two pineapple cultivars were considered: cv. Sugarloaf and cv. Smooth Cayenne. Plant vigor at the time of artificial flower induction was measured by three variates: the number of functional leaves, the D-leaf length and their cross product. Fruit quality attributes measured at harvest time included external attributes (weight and height of fruit, infructescence and crown) and internal quality attributes [total soluble solids (TSS), pH, translucent flesh]. Results showed that the heterogeneity in fruit weight was a consequence of the heterogeneity in vigor of the plants at the moment of flower induction; that effect was mainly on the infructescence weight and less or not on the crown weight. The associations between plant vigor variates at flower induction and the internal quality attributes of the fruit were poor and/or not consistent across experiments. The weight of the slips (side shoots) explained part of the heterogeneity in fruit weight, infructescence weight and fruit height in cv. Sugarloaf. Possibilities for reducing the variation in fruit quality by precise cultural practices are discussed

Analysis of pineapple production systems in Benin

In Benin, pineapple is an important fruit crop, mainly grown in the Atlantic department. The overall quality of the two cultivars grown, ‘Sugarloaf’ and ‘Smooth Cayenne’, does not meet the requirements for some outlets and the heterogeneity in fruit quality within and between lots is high. This paper (1) describes and analyses the pineapple production systems of ‘Sugarloaf’ and ‘Smooth Cayenne’ and (2) identifies the main constraints reducing the quality of pineapple produced. First, semi-structured interviews were carried out with key informants including producers’ organisations, input supplier and extension agents. Next, an in-depth questionnaire was carried out with 100 producers in the Atlantic department. Additionally, pedological and meteorological information was collected. Results indicated that pedo-climatic conditions in the Atlantic department were favourable for pineapple cultivation. The production practices were very diverse for both cultivars, especially regarding planting material used (slips, hapas and suckers), planting density, flowering induction time, and fertiliser application. The production systems of the two cultivars differed in type of planting material used, planting density, use of K2SO4, number of fertiliser applications and ethephon application. In ‘Smooth Cayenne’ cultivation, only hapas and suckers were used, planting density was lower, the number of fertiliser applications was higher, K2SO4 was generally used and maturity was more often synchronised than in ‘Sugarloaf’ cultivation. The main constraints were availability of appropriate planting material, heterogeneity in weight, age and leaf number of planting material, and availability and high costs of fertilisers. Tackling all these constraints would help producers improve the quality of produced pineapple in Benin

Bottlenecks and opportunities for quality improvement in fresh pineapple supply chains in Benin

This study mapped and diagnosed the fresh pineapple supply chains in Benin to identify bottlenecks in pineapple quality improvement for different markets. A research framework was defined that comprised all relevant aspects to be researched. After 54 semi-structured interviews with key informants, 173 structured interviews were held with actor groups. The chain diagnosis showed there was no concordance between actor groups in which quality attribute they valued most. Moreover, pineapple quality was found to be highly heterogeneous. Key bottlenecks identified were lack of training of primary producers in production practices, unconditioned transport, and unavailability of boxes for export

Selective pruning in pineapple plants as means to reduce heterogeneity in fruit quality

Heterogeneity in fruit quality (size and taste) is a major problem in pineapple production chains. The possibilities were investigated of reducing the heterogeneity in pineapple in the field by pruning slips on selected plants, in order to promote the fruit growth on these plants. Slips are side shoots that develop just below the pineapple fruit during fruit development. Two on-farm experiments were carried out in commercial fields in Benin with a cultivar locally known as Sugarloaf, to determine (a) the effect of slip pruning on fruit quality; (b) whether the effect of slip pruning depends on the pruning time; and (c) whether slip pruning from the plants with the smallest infructescences results in more uniformity in fruit quality. A split-plot design was used with pruning time (2 or 3 months after inflorescence emergence) as main factor and fraction of pruned plants (no plants pruned (control); pruning on the one-third plants with the smallest infructescences; pruning on the two-thirds plants with the smallest infructescences; pruning on all plants) as sub-factor. Fruit quality characteristics measured at harvest were the fruit (infructescence + crown) weight and length, the infructescence weight and length, the crown weight and length, the ratio crown length: infructescence length, the total soluble solids, the juice pH and the flesh translucency. Results indicated that pruning of slips of any fraction of the plants at 2 or 3 months after inflorescence emergence did not lead to a consistent improvement in quality or uniformity. Consequently it is not recommended to farmers in Benin to prune the slips

Understanding the effects of slip pruning on pineapple fruit quality

Pineapple fruit quality is important especially when fruits are exported to international markets. Fruits should meet minimum requirements such as a weight of at least 0.7 kg, a ratio between the crown length and infructescence (fruit without the crown) length ranging from 0.5 to 1.5, and a Brix of at least 12. Most pineapple producers in Benin face difficulties in meeting these requirements and thus a very low fraction of the produce is exported. Pruning of pineapple slips has been explored as a means to improve fruit quality but no consistent effects were found. In this study slips were pruned from plants with small and large infructescences and the effects on fruit characteristics were determined. Two on-farm experiments were conducted in commercial fields in Benin using a cultivar locally known as Sugarloaf. Split-plot experiments were used with main plots pruned two or three months after inflorescence emergence and split plots having all slips or no slips pruned. The length of the infructescence on the day of pruning was used to characterise plants as least or most advanced. Fruit attributes measured at harvest were fruit (infructescence + crown) weight and length, and total soluble solids. Fruit and infructescence lengths and weights at harvest were positively related to the length of the infructescence at pruning (IL), and the ratio crown: infructescence length at harvest was negatively related to the IL. Pruning of slips, however, did not increase fruit and infructescence weight and length, nor the total soluble solids, in any of the treatments. Therefore, slip pruning is not an option to increase pineapple fruit and infructescence lengths and weights or the percentage of marketable fruits in Benin

Bottlenecks and opportunities for quality improvement in fresh pineapple supply chains in Benin

This study mapped and diagnosed the fresh pineapple supply chains in Benin to identify bottlenecks in pineapple quality improvement for different markets. A research framework was defined that comprised all relevant aspects to be researched. After 54 semi-structured interviews with key informants, 173 structured interviews were held with actor groups. The chain diagnosis showed there was no concordance between actor groups in which quality attribute they valued most. Moreover, pineapple quality was found to be highly heterogeneous. Key bottlenecks identified were lack of training of primary producers in production practices, unconditioned transport, and unavailability of boxes for export

Analysis of pineapple production systems in Benin

In Benin, pineapple is an important fruit crop, mainly grown in the Atlantic department. The overall quality of the two cultivars grown, ‘Sugarloaf’ and ‘Smooth Cayenne’, does not meet the requirements for some outlets and the heterogeneity in fruit quality within and between lots is high. This paper (1) describes and analyses the pineapple production systems of ‘Sugarloaf’ and ‘Smooth Cayenne’ and (2) identifies the main constraints reducing the quality of pineapple produced. First, semi-structured interviews were carried out with key informants including producers’ organisations, input supplier and extension agents. Next, an in-depth questionnaire was carried out with 100 producers in the Atlantic department. Additionally, pedological and meteorological information was collected. Results indicated that pedo-climatic conditions in the Atlantic department were favourable for pineapple cultivation. The production practices were very diverse for both cultivars, especially regarding planting material used (slips, hapas and suckers), planting density, flowering induction time, and fertiliser application. The production systems of the two cultivars differed in type of planting material used, planting density, use of K2SO4, number of fertiliser applications and ethephon application. In ‘Smooth Cayenne’ cultivation, only hapas and suckers were used, planting density was lower, the number of fertiliser applications was higher, K2SO4 was generally used and maturity was more often synchronised than in ‘Sugarloaf’ cultivation. The main constraints were availability of appropriate planting material, heterogeneity in weight, age and leaf number of planting material, and availability and high costs of fertilisers. Tackling all these constraints would help producers improve the quality of produced pineapple in Benin