Ajit Arun Waman

Micropropagules can Profitably Save the Choicest Silk Banana from Extinction

Panama wilt, a deadly disease of banana in general and Silk group in particular, is creating havoc worldwide. Infected planting material being a major mode of disease spread, production of disease free quality planting material is a must for area expansion. Micropropagation offers a viable solution for overcoming this problem. Though protocols for micropropagation have been standardized for various varieties of banana, their in field trials along with the conventional propagules have seldom been made. This study deals with agronomic, phenological and post harvest attributes of in vitro propagated plantlets of Silk banana var. Nanjanagud Rasabale in comparison to their traditional counterparts. Tissue cultured plantlets were superior to sucker derived plants in terms of vegetative growth, yield and quality parameters. Further micropropagules were precocious by eight weeks and exhibited synchronized flowering.

Not all sugars are sweet for banana multiplication. In vitro multiplication, rooting, and acclimatization of banana as influenced by carbon source-concentration interactions

Carbon sources have been considered as one of the most important factors for in vitro multiplication of excised tissues. The type and concentration of sugars are known to influence the success of any in vitro protocol. In the present investigation, the effect of four carbon sources (glucose, fructose, mannitol, and sucrose) used to supplement Murashige and Skoog medium at three concentrations (1, 2, and 3%) was studied with respect to in vitro multiplication, in vitro rooting, and hardening in ‘Silk’ banana. Fructose (2%) followed by sucrose (3%) were found to be most the congenial carbon sources for obtaining the highest shoot multiplication rates. Growth parameters were also found to be superior in the fructose-containing media; however, it performed poorly in terms of root induction. Whereas, medium containing sucrose (3%) supported 100% root induction of in vitro-derived shoots. Plantlets multiplied initially on glucose-containing (1 and 3%) and sucrose-containing (3%) media exhibited superior growth parameters after secondary hardening. We conclude that a change in the rooting media could improve the number of successfully hardened plants under ex vitro conditions. To our knowledge, this is the first report describing the effect of sugars on hardening-related parameters in AAB genome of banana and apparently on any variety of banana.

Influence of Different Growth Regulators on In Vitro Multiplication of Mixed Diploid Banana (Musa AB)

AbstractThe commercial scale banana multiplication through micropropagation is concentrated mainly on the Cavendish group of bananas. Other varieties, though possess a wide array of desirable characters, have been conveniently neglected owing to their inherent problems such as difficult aseptic establishment, low multiplication rate, culture browning, difficult hardening, etc. The mixed diploid bananas including the Ney Poovan are among the choicest of bananas relished in many parts of the world. To promote its cultivation, systematic studies were undertaken and the lines possessing superior attributes have been identified. In order to multiply the clones in large number, a viable multiplication protocol is a must. The present study dealt with optimizing the plant growth regulator requirements of the growing cultures for obtaining superior multiplication and in vitro rooting. Out of the different cytokinins as benzyl aminopurine, 2-isopentenyl adenine, meta topolin (mT), and thidiazuron (TDZ) tested, only TDZ was found to promote shoot multiplication in both types of propagules i.e. single and double bud explants, although shorter plantlets were noticed in the treatment. In vitro root induction parameters were found to be superior when indole butyric acid was used as auxin source. This report could help in improving the multiplication rate of this least attempted group of bananas. As per the present knowledge it is the first report on the use of TDZ and mT in mixed diploid banana.

In Vitro Shoot Multiplication and Root Induction in Silk Banana Variety Nanjanagud Rasabale as Influenced by Monochromatic Light Spectra

Abstract A number of factors are known to influence the aseptic culture multiplication, rooting and subsequent hardening in banana. Study of these factors would not only improve the in vitro response but also help in increasing the understanding of its basis. During present investigation, in vitro culture proliferation and root induction response in Silk banana as affected by different monochromatic lights (red, white, green and blue) was studied. In multiplication stage, cultures were grown on media with or without supplemental cytokinins. Results revealed that white light promoted shoot multiplication and growth on cytokinin rich media, when compared with other lights studied. Shoot multiplication was also improved in red light as compared to blue and green, but noticeable reduction in the quality of shoots was reported. Incubation of shoots under blue lights improved the quality of the shoots, and the regenerants were uniform in growth. White and blue lights also supported root induction and growth related parameters during in vitro root induction phase. Considering the growth response and uniformity of the cultures, blue light could be effectively used as an option in the slow growth culture in banana, however further investigations could help in optimizing the culture conditions.

Callus culture and plant regeneration from seedling explants in ‘Poshita’ indian ginseng

The study was conducted to establish callus culture and plant regeneration in Withania somnifera (L.) Dunal. cv. Poshita with different explants and different auxin types and concentrations. Nodal explant showed better callusing response irrespective of auxin concentrations supplemented in the media, as compared to epicotyls, hypocotyls, leaves, and root tips. Maximum callusing score of 4.28 was recorded when nodes were cultured on Murashige and Skoog’s (MS) media containing 2 mg · L−1 naphthaleneacetic acid (NAA). Root tip and hypocotyls explants, which were found poor in inducing callus, showed highest proliferation of 6.57 and 6.00, respectively, on media with 2,4-Dichlorophenoxyacetic acid (2,4-D) for subculture. Highest number of shoots (16.0) per explant was obtained from epicotyls and nodes cultured on 1 and 2 mg · L−1 benzyladenine (BA), respectively. Indole-3-butyric acid (IBA) was found to be superior source of auxin for all rooting parameters, except percent rooting. Number of primary roots was found maximum (24.8) with 2.0 mg · L−1 IBA. Irrespective of auxin used, the length of primary root decreased with increase in concentration, maximum (6.18 cm) being in media with 0.5 mg · L−1 IBA. Plantlets were best hardened when agropeat was used as a substrate.

In search of commercially acceptable Panama wilt-resistant natural variants in Ney Poovan banana (Musa AB)

Ney Poovan banana, the most widely cultivated mixed diploid banana, has been reported to be susceptible to Fusarium wilt like many other varieties in the world. The identification of natural variants possessing disease tolerance or resistance is one strategy to prevent losses. The aim of this study was to identify resistant lines in Ney Poovan banana, through extensive field surveys and screening of putative variants using a detached leaf-based challenging technique. The selected lines were screened under field condition to determine their economic feasibility for commercial-scale use. A total of 26 lines were observed to be resistant to the disease, out of which 24 exhibited a commercially acceptable productivity index and five best lines possessing desirable attributes were obtained.

Preliminary Investigations on Identification and Evaluation of Early and Dwarf Lines of Ney Poovan Banana (Musa AB) for Commercial Scale Utilization

Ney Poovan is a group of elite mixed diploid bananas characterized by superior dessert quality and agronomic attributes. However, its commercial scale cultivation is largely jeopardized due to tall stature and longer crop duration than the commercial counterparts such as Cavendish bananas. Surveys were thus carried out in banana growing regions of Karnataka, India with the objective to identify short and precocious natural variants. The exhaustive surveys yielded a number of superior clones with near-idiotypic characteristics. Significant diversity existed among the 37 lines evaluated for traits such as plant stature, cropping cycle, yield contributing characters and productivity index. The discussed pragmatic approach involving exploration and utilization of the existing diversity was not only helpful in addressing the aforesaid problems but could also form the basis for rapid crop improvement in other long duration varieties of banana.

Key Phenological Events, their Practical Implications and Effect of Bunch Age on Physico-Chemical and Postharvest Attributes in Ney Poovan Banana ( Musa AB)

Banana, one of the major staple food crops of the world, flowers round the year irrespective of the season. It gives the decisive flexibility to the grower for planning orchard operations as well as exploring the best marketing opportunities for the produce well in advance. Being a heavy feeder of nutrients and water, these inputs are critical to the success of banana cultivation especially at reproductive stage. Also, banana fruits are sensitive to many biotic and abiotic stresses which render them unsuitable for marketing. All these factors could be taken care of if phenological cycle of the crop is known to the grower. In Ney Poovan (Musa AB) banana, 58 plants were studied for parameters like days taken for floral initiation, anthesis, completion of female phase, fruit filling and total crop duration using BBCH scale. Inflorescence appeared after 311 days of planting and duration of reproductive stage varied between 124–147 days with average crop duration of 443 days. An account of the practical implications of this study has been discussed in detail. Further, another study was conducted in order to study the changes in the quality and storage behavior of the fruits harvested at different phases of bunch development (12–18 weeks after anthesis). Studies revealed that fruits harvested after 16 weeks of anthesis were more firm, exhibited maximum shelf life with minimum PLW and had highest TSS content amongst all the groups studied. The early as well as delayed harvesting rendered the fruits inferior in most of the parameters studied.ZusammenfassungDie Banane, eines der Hauptnahrungsmittel der Welt, blüht, unabhängig von der Jahreszeit, während des ganzen Jahres. Diese Eigenschaft ermöglicht dem Anbauer, die Obstproduktion zu planen und die besten Vermarktungsmöglichkeiten für das Produkt im Voraus zu erkunden. Dadurch, dass Bananen einen hohen Nährstoff- und Wasserbedarf haben, sind diese Faktoren besonders während der Fruchtbildungsphase entscheidend für den Erfolg der Bananenkultur. Bananen reagieren ebenfalls empfindlich auf biotischen und abiotischen Stress, der zu unzureichenden Vermarktungsqualitäten führen kann. Alle diese Faktoren können berücksichtigt werden, wenn sich der Anbauer mit dem phänologischen Zyklus auskennt.58 Pflanzen der Bananensorte ‚Ney Poovan‘ (Musa, AB) wurden auf Parameter wie Tage bis zum Blühbeginn, Anthese, Beendigung der weiblichen Phase, Fruchtbildung und Reifestadien unter Zuhilfenahme der BBCH-Skala untersucht. Der Blütenstand erschien 311 Tagen nach der Pflanzung, die generative Phase lag zwischen 124 und 147 Tagen. Von der Pflanzung bis zur Ernte vergingen durchschnittlich 443 Tage. Die praktischen Schlussfolgerungen dieser Studie werden berichtet und ausführlich diskutiert.Darüber hinaus wird eine weitere Studie ausgeführt, die sich mit der Qualitätsveränderung und dem Lagerverhalten der in verschiedenen Entwicklungsphasen geernteten Bananenbüschel (12 bis 18 Wochen nach der Anthese) befasst. Studien zeigten, dass die Früchte, die 16 Wochen nach der Anthese geerntet wurden, weniger fester waren und ein größtmögliches Shelf Life mit kleinstem physiologischen Gewichtsverlust (PLW) und höchstem Trockensubstanzgehalt (TSS) innerhalb aller geprüften Varianten aufwiesen. Die zu frühe als auch die zu späte Ernte führte zu geringeren Fruchtqualitäten.