Selection of cooking banana genotypes for yield and black Sigatoka resistance in different locations in Uganda

It is imperative to systematically evaluate new banana genotypes in different locations before national release. This enables selection and recommendation of superior genotypes as new varieties for a wider range of environments. The objective of the present study was to select banana genotypes with stable and high performance for bunch yield and leaf black Sigatoka resistance. Eleven cooking banana genotypes developed by the Uganda National Agricultural Research Organization in collaboration with Bioversity International, and two check varieties were evaluated in multi-location preliminary yield trials in Uganda. Data collected were analyzed using Additive Main Effects and Multiplicative Interaction (AMMI) model, AMMI Stability Value, and Genotype Selection Index (GSI). Genotype × location interaction was significant for all the traits assessed. Most of the new genotypes had low interaction effects with locations for bunch yield (69.2%) and black Sigatoka (92.3%). The most stable genotypes for bunch yield were NABIO815, NABIO1117, NABIO216 and NABIO306 whereas for black Sigatoka resistance, were NABIO1011, NABIO815, NABIO1009 and NABIO216. Using the GSI that defines the most desirable genotypes as those that combine high agronomic performance and stability across environments, four genotypes (NABIO306, NABIO1011, NABIO808 and NABIO1009) were selected. These genotypes, in addition to their high performance for agronomic traits and stability, had soft and yellow fruit pulp on cooking, and will be advanced on farm for further evaluatio

MGIS: managing banana (Musa spp.) genetic resources information and high-throughput genotyping data

Unraveling the genetic diversity held in genebanks on a large scale is underway, due to advances in Next-generation sequence (NGS) based technologies that produce high-density genetic markers for a large number of samples at low cost. Genebank users should be in a position to identify and select germplasm from the global genepool based on a combination of passport, genotypic and phenotypic data. To facilitate this, a new generation of information systems is being designed to efficiently handle data and link it with other external resources such as genome or breeding databases. The Musa Germplasm Information System (MGIS), the database for global ex situ-held banana genetic resources, has been developed to address those needs in a user-friendly way. In developing MGIS, we selected a generic database schema (Chado), the robust content management system Drupal for the user interface, and Tripal, a set of Drupal modules which links the Chado schema to Drupal. MGIS allows germplasm collection examination, accession browsing, advanced search functions, and germplasm orders. Additionally, we developed unique graphical interfaces to compare accessions and to explore them based on their taxonomic information. Accession-based data has been enriched with publications, genotyping studies and associated genotyping datasets reporting on germplasm use. Finally, an interoperability layer has been implemented to facilitate the link with complementary databases like the Banana Genome Hub and the MusaBase breeding database. Database URL:https://www.crop-diversity.org/mgis

Effect of Preparation and Drying Techniques on the Physicochemical, Functional and Nutritional Properties of products from Beetroot (Beta Vulgaris L.) varieties

Beetroot (Beta vulgaris L.) is rich in biologically active compounds. This study aimed to assess how different methods of preparation and drying affect the physical, chemical, functional, and nutritional properties of iron-rich beetroot powder. Two beetroot varieties, Detroit Dark Red (DetR) and Crimson Globe (CrimG), were processed using three drying techniques: sun drying (SD), oven drying (OD), and freeze drying (FD), with both boiled and fresh beetroots. The properties evaluated in the study included water activity, color, total phenolics and flavonoids, oxalate content, and mineral content. The results showed significant (p<0.05) differences in these properties between the dried and fresh samples. Notably, drying increased calcium, zinc, and phosphorus levels while decreasing the iron content. Boiling followed by sun drying was the best method for retaining iron, particularly for the CrimG variety. The study suggests that drying can help preserve or even enhance the physicochemical properties and micronutrient content, especially iron while reducing phytochemical levels affecting iron absorption. These findings are important for developing iron-rich beetroot products to improve dietary iron intake, especially for adolescent children

Use of timelapse photography to determine flower opening time and pattern in banana (Musa spp.) for efficient hand pollination

Open Access Journal; Published online: 30 Sep 2021Sterility and low seed set in bananas is the main challenge to their conventional genetic improvement. The first step to seed set in a banana breeding program depends on pollination at the right time to ensure effective fertilization. This study aimed at determining bract opening time (BOT) to enhance efficient pollination and seed set in bananas. A Nikon D810 digital camera was set-up to take pictures of growing banana inflorescences at five-minute intervals and time-lapse movies were developed at a speed of 30 frames per second to allow real-time monitoring of BOT. Genotypes studied included wild banana (1), Mchare (2), Matooke (4), Matooke hybrid (1), and plantain (1). Events of bract opening initiated by bract lift for female flowers (P < 0.01) started at 16:32 h and at 18:54 h for male flowers. Start of bract rolling was at 18:51 h among female flowers (P < 0.001) and 20:48 h for male flowers. Bracts ended rolling at 02:33 h and 01:16 h for female and flowers respectively (P < 0.05). Total time of bract opening (from lift to end of rolling) for female flowers was significantly longer than that of male flowers (P < 0.001). On average, the number of bracts subtending female flowers opening increased from one on the first day, to between one and four on the fourth day. The number regressed to one bract on day eight before start of opening of bracts subtending male flowers. There was a longer opening interval between bracts subtending female and male flowers constituting spatial and temporal separation. Bract rolling increased from partial to complete rolling from proximal to the distal end of the inflorescence among female flower. On the other hand, bracts subtending male flowers completely rolled. Differences in BOT of genotypes with the same reference time of assessment may be partly responsible for variable fertility. Hand pollination time between 07:00 and 10:00 h is slightly late thus an early feasible time should be tried

Development of two high-yielding, consumer-acceptable apple banana hybrids (Musa species, AAB genome group) with resistance to Fusarium oxysporum f. sp. cubense race 1

Fusarium wilt of bananas (Musa species) is caused by Fusarium oxysporum f. sp. cubense (Foc). Foc race 1 in particular affects dessert bananas in Uganda, causing >60% yield loss. This study was conducted to assess the performance of two new apple banana genotypes for bunch yield, resistance to Foc race 1 and consumer acceptability. The new apple banana genotypes (NAMU1 and NAMU2), along with two check cultivars, one susceptible but preferred by consumers (Sukali ndiizi) and the other resistant (Yangambi-KM5), were evaluated at the National Agricultural Research Laboratories in Uganda. Bunch yields of the two new apple bananas were higher than those of check cultivars by >50%. NAMU1 and Yangambi-KM5 showed no symptoms of Foc race 1, whereas NAMU2 showed mild symptoms on its corms. Sukali ndiizi showed severe pseudostem splitting and corm discoloration as the key symptoms of Foc race 1. The consumer acceptability of NAMU1 and NAMU2 was as high as that of Sukali ndiizi, implying that they can be perfect substitutes for the Foc race 1 susceptible Sukali ndiizi

Changes In Microstructure, Beta Carotene Content And In Vitro Bioaccessibility Of Orange-Fleshed Sweet Potato Roots Stored Under Different Conditions

Orange-fleshed sweet potatoes {OFSP} (Ipomoea batatas (L.) Lam) contain high levels of beta carotene, an important provitamin A carotenoid. Stored sweet potato roots undergo many physiological changes that affect their beta carotene content and bioaccessibility as well as the tissue microstructure. This study investigated the changes in microstructure, beta carotene content and in vitro bioaccessibility of stored OFSP roots. Roots of two varieties of OFSP, Ejumula and SPK004/6/6 were each stored under the following conditions: in a pit (17-21 o C, RH 90-100%), saw dust (19-23 o C, RH 86-100%), dark room (24.5-28 o C, RH 68-100%) and ambient (24-27 o C, RH 68-100%). Samples were drawn monthly from each of the storage treatments and analyzed for changes in beta carotene content, in vitro bioaccessibility and tissue microstructure. Stored roots of Ejumula variety contained significantly more (P ≤ 0.05) beta carotene than those of the SPK004/6/6 variety. There was no significant difference (P ≥ 0.05) between varieties in regards to beta carotene bioaccessibility. Roots stored in pits retained higher beta carotene content compared to roots stored under other conditions. In vitro bioaccessibility was significantly higher (P ≤ 0.05) in roots stored in pits compared to roots stored under saw dust, dark room and ambient conditions. Samples of OFSP roots stored under ambient and dark room conditions retained the least amount of beta carotene and had the least amount of bioaccessible beta carotene. There was an increase in the level of cell wall lignification during storage of OFSP. The extent of lignification varied with storage method used. The roots stored under ambient and dark room conditions showed higher levels of lignification compared to those stored under sawdust and in pits. There were no differences in lignification between the different varieties studied. The study shows that storage of OFSP roots using methods that maintain low temperatures leads to higher retention of beta carotene and maintains higher in vitro bioaccessibility

Changes In Microstructure, Beta Carotene Content And In Vitro Bioaccessibility Of Orange-Fleshed Sweet Potato Roots Stored Under Different Conditions

Orange-fleshed sweet potatoes {OFSP} (Ipomoea batatas (L.) Lam) contain high levels of beta carotene, an important provitamin A carotenoid. Stored sweet potato roots undergo many physiological changes that affect their beta carotene content and bioaccessibility as well as the tissue microstructure. This study investigated the changes in microstructure, beta carotene content and in vitro bioaccessibility of stored OFSP roots. Roots of two varieties of OFSP, Ejumula and SPK004/6/6 were each stored under the following conditions: in a pit (17-21 o C, RH 90-100%), saw dust (19-23 o C, RH 86-100%), dark room (24.5-28 o C, RH 68-100%) and ambient (24-27 o C, RH 68-100%). Samples were drawn monthly from each of the storage treatments and analyzed for changes in beta carotene content, in vitro bioaccessibility and tissue microstructure. Stored roots of Ejumula variety contained significantly more (P ≤ 0.05) beta carotene than those of the SPK004/6/6 variety. There was no significant difference (P ≥ 0.05) between varieties in regards to beta carotene bioaccessibility. Roots stored in pits retained higher beta carotene content compared to roots stored under other conditions. In vitro bioaccessibility was significantly higher (P ≤ 0.05) in roots stored in pits compared to roots stored under saw dust, dark room and ambient conditions. Samples of OFSP roots stored under ambient and dark room conditions retained the least amount of beta carotene and had the least amount of bioaccessible beta carotene. There was an increase in the level of cell wall lignification during storage of OFSP. The extent of lignification varied with storage method used. The roots stored under ambient and dark room conditions showed higher levels of lignification compared to those stored under sawdust and in pits. There were no differences in lignification between the different varieties studied. The study shows that storage of OFSP roots using methods that maintain low temperatures leads to higher retention of beta carotene and maintains higher in vitro bioaccessibility

Evaluation of Mchare and Matooke Bananas for Resistance to Fusarium oxysporum f. sp. cubense Race 1

Fusarium wilt, caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (Foc) race 1, is a major disease of bananas in East Africa. Triploid East African Highland (Matooke) bananas are resistant to Foc race 1, but the response of diploid (Mchare and Muraru) bananas to the fungus is largely unknown. A breeding project was initiated in 2014 to increase crop yield and improve disease and pest resistance of diploid and triploid East African Highland bananas. In this study, eight Mchare cultivars were evaluated for resistance to Foc race 1 in the field in Arusha, Tanzania. In addition, the same eight Mchare cultivars, as well as eight Muraru cultivars, 27 Mchare hybrids, 60 Matooke hybrids and 19 NARITA hybrids were also screened in pot trials. The diploid Mchare and Muraru cultivars were susceptible to Foc race 1, whereas the responses of Mchare, NARITAs and Matooke hybrids ranged from susceptible to resistant. The Mchare and Matooke hybrids resistant to Foc race 1 can potentially replace susceptible cultivars in production areas severely a ected by the fungus. Some newly bred Matooke hybrids became susceptible following conventional breeding, suggesting that new hybrids need to be screened for resistance to all Foc variants.status: Published onlin