Rapid Multiplication Techniques Research Articles

Ex vitro rooting of micro-propagated intergeneric papaya through phloroglucinol

Micropropagation techniques of papaya have been optimized Worldwide. However, standard rapid multiplication technique of papaya at commercial level with economically viable is still lacking. Since establishment of in vitro culture pretty easy at the same time in vitro rooting of papaya is still difficult. However, in vitro rooting is costly and the roots initiated in vitro do not have lateral branches and root hairs, making them difficult to acclimatize. Hence ex vitro rooting induction of micro-propagated plantlets and acclimatization were conducted. In vitro cultures were established using shoot tips from seedlings of selected advanced intergeneric hybrid. They were inoculated onto Murashige and Skoog (MS) medium + 3% sucrose + 1 µM BAP + 1 µM GA3 + 0.1 µM IAA + 0.25% phytagel until plantlets were obtained. For ex vitro rooting, plantlets were cultured with various concentrations of phloroglucinol (PG) to investigate the appropriate condition of rooting. Direct rooting (82%) of papaya micro-cutting into potting medium (perlite + vermiculite + coco peat; in the ratio of 1:1:2) subsequent dipping into phloroglucinol was more effective than in vitro rooting and led to amended survival percentage (82%) of micro-cutting during acclimatization. PG at 1000 µM was extra effectual than IBA in encouraging root development. Sachet method was found to be the best appropriate for ex vitro rooting and hardening of papaya with single-step acclimatization.

Production and availability of good quality seed potatoes in the East African region: A review

Demand for potatoes has grown rapidly in eastern Africa due to rapid population growth, urbanisation and life style changes. This has made potato an important commodity crop in the region contributing to food security and enhanced livelihoods. However, potato productivity in the region is low; ranging from 6 to10 t/ha against potential yields of over 30 t/ha. One of the major causes of low yields is the chronic shortage of good quality seed potatoes for planting, which also limits adoption of new and improved varieties. Therefore, the objective of this paper is to highlight the opportunities and progresses in the production and availability of good quality seed potatoes in the East African region to bolster the productivity and commercial value of the crop. The first section of the paper discusses the status of good quality seed potatoes production and availability in the East African region. The second section looks at the farmer-based seed potato production technologies while the third section focuses on the efforts of both the private and public sector in production of good quality seed potatoes. Availability of good quality seed potatoes constitutes < 1% of the requirement in eastern Africa. These seeds are mainly produced by public research institutions as well as some private players. Consequently, most farmers opt to plant seed potatoes from informal sources. However, seeds from informal sources are mostly of poor quality and often accelerate the spread of tuber-borne diseases, especially viruses and bacterial wilt. To improve seeds from informal system, some technologies have been identified and promoted to enhance farmer-based seed production and distribution. These include seed plot technology (SPT), positive selection techniques (PST) and Quality Declared Seed (QDS) systems. In addition, there has been adoption and promotion of rapid multiplication techniques (RMT) such as stem/shoot cuttings, aeroponics, sandponics, and hydroponics among others. Other measures that have been taken include importing seeds of new potato varieties. The imports increase the quantity of seeds and the number of potato varieties available to farmers. Despite these efforts, the quantity of good quality seeds available is still far below the requirements. There is need for the governments, private sector players as well as farmers to enhance their efforts and save the situation. Governments need to invest seriously in local breeding activities and multiplication of early generation seeds. These and other measures may increase availability of good quality and affordable seed potatoes in East African region.

Application of Rapid Multiplication Technique Using Mini Cutting and NPK Compound Fertilizer to Increase Production of Sweet Potato Cuttings (Ipomoea batatas L.)

Rapid Multiplication Technique (RMT) is a technique used to produce large scale cuttings of sweet potato in a short period by using mini cuttings and proper fertilizer management. The research was carried out from October 2019 to March 2020 and composed of two experiments The first experiment involved a randomized complete block design, with clones (“Ase Kapas” and “Ase Merah”) as the first factor, and tuber weight (150 ± 25 g, 250 ± 25 g, and 350 ± 25 g) as the second factor. The second experiment was arranged in a split-plot design involving different doses of NPK compound fertilizer (as main plot) and different source of cuttings (as subplots). The different doses included NPK 16:16:16 at 100 kg.ha-1 (0.3 g per polybag), 200 kg.ha-1 (0.6 g per polybag), 300 kg.ha-1 (0.9 g per polybag), and without fertilizer as control. The source of cuttings were from the tip, middle and bottom stem of the plants. Results showed that the “Ase Kapas” showed the highest number and the longest shoots, number of nodes, and length of vines. Additionally, tuber weight of ± 350 g produced the highest number of shoots. When it comes to NPK compound fertilizer treatment, a dose of 0.9 g per polybag increased cutting production in “Ase Kapas”, and also responded better to fertilizer treatment. On the other hand, dose of 0.3 g increased cutting production in “Ase Merah”. “Ase Kapas” produced more cuttings from the middle stem, whereas “Ase Merah” produced more cuttings from the . The application of RMT in “Ase Kapas” produced cuttings with ratio of 1:31, which is higher than those in “Ase Merah” with a ratio of 1:17.

Participatory Improved Potato Technology Promotion: The Case of Smallholder Farmers in North, West and Southwestern Highlands of Ethiopia

Utilization of healthy planting material is a key factor to improve potato yields to reduce the dissemination of diseases and pests. Quality seed is one of the major bottlenecks hindering the production and productivity of potato in major potato growing regions of the country. Therefore, participatory on-farm seed production and improved potato technologies promotion have been carried out during the year 2014-2016 at five districts, Jeldu, Dendi, Wolmera Degem and Kersana Malima of central Ethiopia. To produce quality potato seed various rapid multiplication techniques were used. Thus, improved potato technologies were demonstrated using different methodologies such as the farmers’ field schools, the farmers' research group and field days. To supply clean tubers about 138,886 high-quality mini-tubers of improved varieties of Belete, Gudanie, Jalenie and Awash were produced. Moreover, a total of 257.08 tons of seed tubers of 15 released potato varieties were produced and disseminated in different parts of the country for research and developments. The participant farmers produce 442.9 tons of relatively clean seed tubers and sold to different parts of the country. During, this activity positive selection technique was demonstrated and participant farmers applied the techniques that helped them to improve the yield and quality of seed potato. Farmers obtained a 40% yield increase and a 33% vigour improvement when positive selection techniques were applied. Training on improved potato production and postharvest handling technologies have also been given for farmers, development agents, agricultural experts and home agents. Therefore, decentralized quality seed production reduces the movement of dangerous diseases like bacterial wilt and viruses from invading areas with high potential for seed production due to purchase of seed only from within one’s same region.

Soft wood grafting - A novel and rapid multiplication technique in Coorg mandarin (Citrus reticulate Blanco)

Coorg mandarin is commercially multiplied by shield or T budding. The process of shield budding will takes eighteen to twenty months for the production of quality planting material. Hence present experiment was conducted to standardize soft wood grafting in Coorg mandarin to reduce the nursery phase for rapid multiplication of quality planting materials. In this study, two to three months old terminal shoots of Coorg mandarin were grafted on one, two, three and four months old rootstocks of Rangpur lime.The soft wood grafting on three and four months old rootstocks were recorded cent per cent graft success and higher plant survivability (98%) and minimum was noticed in one month old rootstocks. The plant height (45.77 cm), plant girth (0.60 cm), number of leaves per plant (42.9), number of side shoots per plant (5.65), root length (33.15 cm) and root spread (8.29 cm)were also found maximum on four months old root stocks followed by three month old rootstocks. Age of rootstocks have significant difference (P=0.05) for plant weight, shoot weight and root weight in both fresh and dry weight basis.The above findings revealed that, four months old rootstocks are more suitable for soft wood grafting in terms of graft success and plant traits. Soft wood grafting can be gainfully exploited for rapid multiplication of good quality planting material by reducing the nursery phase.

Soft wood grafting - A novel and rapid multiplication technique in Coorg mandarin (Citrus reticulate Blanco)

Coorg mandarin is commercially multiplied by shield or T budding. The process of shield budding will takes eighteen to twenty months for the production of quality planting material. Hence present experiment was conducted to standardize soft wood grafting in Coorg mandarin to reduce the nursery phase for rapid multiplication of quality planting materials. In this study, two to three months old terminal shoots of Coorg mandarin were grafted on one, two, three and four months old rootstocks of Rangpur lime.The soft wood grafting on three and four months old rootstocks were recorded cent per cent graft success and higher plant survivability (98%) and minimum was noticed in one month old rootstocks. The plant height (45.77 cm), plant girth (0.60 cm), number of leaves per plant (42.9), number of side shoots per plant (5.65), root length (33.15 cm) and root spread (8.29 cm)were also found maximum on four months old root stocks followed by three month old rootstocks. Age of rootstocks have significant difference (P=0.05) for plant weight, shoot weight and root weight in both fresh and dry weight basis.The above findings revealed that, four months old rootstocks are more suitable for soft wood grafting in terms of graft success and plant traits. Soft wood grafting can be gainfully exploited for rapid multiplication of good quality planting material by reducing the nursery phase.

Accelerating Seed Potato Production By Using Rapid Multiplication Systems in Ethiopia

Ethiopia is one of the major potato producing countries of the Sub-Saharan Africa region where potato is the fastest expanding food crop. The natural environment in Ethiopia is very suitable for year round production of potato using rain-fed and irrigated systems. However, the actual potato yield in the country ranges between 8-10 t/ha, which is slightly below the average for Africa. Shortage of good quality seed has been recognized as the single most important factor limiting potato production in the developing countries including Ethiopia. Therefore, the objective of this paper is to review the accelerating role of rapid seed potato multiplication technologies for potato seed production in Ethiopia. A low adoption of recommended seed potato technologies in the country could be due to a lack of alternative seed potato production methods compatible with farmers’ economic and agro-ecological conditions. Since 2010, Holetta Agricultural Research Centre in collaboration with International Potato Center together are applying different seed potato production hastening schemes to produce early generation seed. These seed multiplication schemes include, tissue culture, aeroponics, sand hydroponics and other rapid multiplication methods in screen house pots. These seed potato multiplication schemes brought a dynamic change for the last five years by accelerating the supply efficiency by 7.6% with enhancing the number from 43,773 mini-tubers to 332,485 mini-tubers. Moreover, these new seed multiplication schemes enhanced the capacity of clean seed production of the country by producing 216,717 mini-tubers of high quality seed from aeroponics and sand hydroponics. The farmers could also access early generation clean seed potato through their nearby cooperatives with affordable price and with lowtransportation cost. Thus, for developing countries like Ethiopia where formal seed system is at infant stages and early generation seed is mostly produced by research institutions, the use of various rapid multiplication techniques could be one option to produce clean seed potato.

Effect of Some Treatments on Improving Seed Multiplication Ratio in Potato by Stem Cutting

A procedure for rapid multiplication technique of potato using stem cuttings induced to grow at the leaf nodes by removal the apical growing point is described. Sequential five experiments were conducted in the greenhouses and in the field of a private farm (Nubaria district, Bahaira Governorate, Egypt), during the period from 2012 to 2015. In the first experiment, the number of stem cuttings in the different tested cultivars ranged from 16.25 (cv. Patrones) to 38.50 (cv. Spunta). In the second experiment, the rooting hormone K-IBA improved root initiation and development of Spunta cv. and increased survival, root dry weight and quality, additionally had the highest values of tuber yield. The rate of multiplication was 400: 1 against 9: 1 for the conventional method. In the third experiment, a rooting substrate of sand: peat (1:1) enhanced survival, improved growth, yield attributes and M.R. In the fourth experiment, incidence of common potato viruses (PVX, PVY, PLRV and TRV) was negative in second generation of tubers when stem cutting technique was used. In the field study of the fifth experiment, the tuber yields and quality with rooted cuttings were statistically similar for crops from imported seed tubers, however, the proportion of marketable tubers (> 60 mm diameter) was approximately 59% and 50% less in the crops from rooted cutting and tubers from stem cutting, respectively, compared with those from imported seed tubers. Rooted stem cuttings gave the highest net profit. These results indicate that the stem cuttings and small tuber derived from stem cutting are two methods of growing potatoes, which need to be further evaluated for socio-economic assessment by farmers.

Rapid Multiplication Techniques (RMTs): A Tool for the Production of Quality Seed Potato (Solanum tuberosum L.) in Ethiopia

Rapid Multiplication Techniques (RMTs): A Tool for the Production of Quality Seed Potato (Solanum tuberosum L.) in Ethiopia

Use of aeroponics technique for potato (Solanum tuberosum ) minitubers production in Kenya

In Kenya, potato productivity is severely constrained by limited high quality seed tubers; this is precipitated by inefficiencies in various stages in the seed production system. Production of certified seed starts with meristem tip cuttings in the tissue culture. The resultant plantlets are grown in pots in the greenhouse and/or screen-house for production of minitubers (generation 0). In Kenya, production of minitubers through aeroponics systems has been introduced. This paper discusses the production of potato minitubers using aeroponics. Important considerations that should be addressed before setting-up an aeroponics based potato minituber production system are also discussed. Research areas to optimize production and improve field performance of mini-tubers produced through aeroponics are also presented. Key words: Aeroponics, clonal multiplication, hydroponics, minituber production, rapid multiplication techniques, tissue culture.

FACTORS AFFECTING THE ADOPTION OF DISEASE-RESISTANT PLANTAIN AND BANANA (MUSA SPP.) HYBRIDS IN NIGERIA

ISHS IV International Symposium on Banana: International Conference on Banana and Plantain in Africa: Harnessing International Partnerships to Increase Research Impact FACTORS AFFECTING THE ADOPTION OF DISEASE-RESISTANT PLANTAIN AND BANANA (MUSA SPP.) HYBRIDS IN NIGERIA

Sprout and top-shoot cutting for rapid multiplication of potato in Bangladesh

The combined effect of two rapid multiplication techniques (sprout and top-shoot cutting) was assessed using four Dutch potato cultivars during 1991/92–1993/1994 at the Tuber Crops Research Centre (TCRC), Bangladesh Agricultural Research Institute (BARI), Gazipur-1701, Bangladesh. On average, a 70–80 g tuber produced 29 sprout cuttings which were subsequently used for taking top-shoot cuttings. Top-shoot cuttings were taken at a number of dates from 25 November and continued at 10 day intervals, thereafter, until 15 January. The number of top-shoot cuttings produced by 29 sprout cutting-derived plants varied (P<0·01) from 761 to 663 across the cultivars. Cardinal gave the greatest yield. Most of the characters studied varied (P<0·01) between cultivars but not over years while the interaction between cultivars and years was significant (P<0·01).Early planted top-shoot cuttings produced more tubers per plant (4·0) with a greater mean tuber weight (>22 g) than from the late planting (1 tuber and 5·5 g). On average, about 2·8 tubers per plant were produced with a mean tuber weight of 15·8 g. Cardinal and Patrones produced the most tubers per plant (2·9) and Diamant the greatest mean tuber weight (16·8 g). Cardinal gave the greatest yield (P<0·01) of tubers (268) followed by Patrones (241). The 29 sprout cutting plants derived from a 70±5 g tuber produced 160 tubers while the 771 top-shoot plants derived from 29 sprout cutting-derived plants produced 1420 tubers. The rate of multiplication of the combined two RM techniques was 1580[ratio ]1 against 11[ratio ]1 for the conventional method.

EXPERIENCIAS DE LA APLICACIÓN COMERCIAL DE LA TÉCNICA DE REPRODUCCIÓN ACELERADA DE SEMILLA (TRAS) EN PLÁTANO EN RIVAS Y NANDAIME

La multiplicación convencional del plátano (Musa spp.)a través de los hijuelos del cormo, además de la bajatasa de propagación, facilita la diseminación de plagas yenfermedades. La técnica de reproducción acelerada desemillas (TRAS), una alternativa en la producción sana desemilla, fue utilizada para la multiplicación de los cultivaresPlátano Enano (PE) y CENSA ¾ (C ¾) en dos viveroscomerciales de Rivas y Nandaime donde se establecieron 19canteros en cada uno. En Rivas se multiplicaron 3 933 cormosde PE y 2 307 de C ¾ a 2.5 cm entre cormos en sustratosde arena de construcción (AC) y arena de playa (AP), riegopor microasperción y fertilizacion con completo (15-15-15)NPK. En Nandaime se propagaron 6 952 cormos de PE a 1.5cm entre cormos en AC. Se regó con regadoras y manguerasy se fertilizó con Súper fértil y Súper calcio. En Rivas lasplantas separadas de los cormos se sembraron en bolsas depolietileno, en mezcla de cascarilla de arroz-arena-tierra y enNandaime en 100% tierra. Se calculó el índice de brotación(IB) de los cormos. En Rivas el IB de PE fue 4 e igualmentepara C ¾. El IB de PE en Nandaime fue 3. El mejor IB de PEen Rivas resulta de la utilización inmediata de cormos frescosy yemas en mejor estado físico. El IB de PE en AC fue 5 y 3en AP, la diferencia la explica el mayor contenido de cenizasvolcánicas, minerales y capacidad de absorción de agua deAC. Se produjeron 17 039 plantas de PE y 9 052 de C ¾ enRivas y 21 637 plantas de PE en Nandaime. Los IB obtenidosson inferiores a los de la guía técnica-UNA. No se siguieronlas indicaciones de selección de semilla en el campo, distanciade siembra y momento de corte.Palabras clave: TRAS; plátano; índice de brotación; aplicación comercialDOI: 10.5377/calera.v9i13.17