Patch Budding Research Articles

INNOVATIVE METHODS OF WALNUT PRODUCTION IN SOUTH AMERICA

Chile and Argentina are the main walnut producers in South America. Chile has 14,400 hectares and Argentina nearly 18,000. The walnut areas are located in many valleys, along both countries. Growing conditions range from dry and warm climatic conditions, in the north, to rainy and cold summers in the south. In Argentina, where walnut groves are submitted to more extreme climatic conditions, they are present from Catamarca in the north, to Viedma in the south (a distance of close to 2,500 kilometers). In Chile walnut plantations go from Ovalle to Los Angeles (900 kilometers from north to south). All the production requires irrigation. Irrigation systems, and overcoming problems associated with this technology are very important in the success of this industry. In the same way, frost, wind, and rain damage are important production limitations that need to be managed. Both countries began commercial walnut industry when grafting methods were developed, beginning of the 1980's. In Chile patch budding is the most popular nursery system, but in Argentina, lateral grafting on 2- or 3-year-old rootstock is the most common way to establish a new orchard. The most important varieties in Chile are 'Serr' and 'Chandler', with a smaller area planted to 'Howard' and 'Vina' seedlings. Argentina has focused its industry mainly on 'Chandler'. 'Serr' in Chile requires avoidance of PFA (Pistillate Flower Abscission), which varies from 20 to 80% depending the season. Trials carried out in the country have substantially improved fruit production. Management methods for pruning and training, plant nutrition, irrigation, pest and disease control are well developed in South America. However, root and collar rot, walnut blight, codling moth and mites are permanent problems. Presently, no blackline or Armillaria problems are present in either country. Mechanical harvest and controlled dehydration are rapidly being developed, in order to export high quality walnuts to the Northern Hemisphere.

Improved Success of Persian Walnut Grafting Under Environmentally Controlled Conditions

Different budding methods (patch, shield and chip) were compared under controlled and field conditions using different native varieties of Persian walnut (Juglans rejia L.) during June 2005, in Nieriz, Fars province, Iran. Controlling temperature and humidity in a greenhouse improved grafting success considerably in all grafting methods compared with results under field conditions. The highest success rate was obtained with patch (91.0%) followed by shield (31.1%) and chip (19.1%) budding under greenhouse conditions versus 25.0, 15.0 and 10.0% under field conditions, respectively. Similar trends were also observed for callus formation and scion growth. Patch budding showed the highest callus formation and scion growth followed by shield and chip budding under both conditions. The genotype used did not affect grafting take using shield and patch budding excluding the N3 selection which had the highest graft success using the shield budding under greenhouse conditions. The best results were obtained by patch budding, under greenhouse conditions in all of the tested genotypes.

Improving brown budding efficiency in cacao, Theobroma cacao L.: effects of twig manipulation and some control treatments of fungal infection on new sprouts

The very low level of success (about 15%) in patch budding of cacao, Theobroma cacao L. in the West African sub-region has been attributed to poor union success and deaths of new sprouts due to fungal infection. Trials at Cocoa Research Institute of Nigeria (CRIN) headquarters, Ibadan (Lat. 07°10′N Long. 03°52′E at alt. 122 m above mean sea level) showed that twig manipulation methods significantly affected bud-take ( p<0.0001). The ringing method applied to twigs 2 days before actual budding gave significantly ( p<0.05) more initial bud-take (70.0%) than the conventional method (54.0%). A dip treatment of budwood for 3 min in a solution of benomyl-active (Benlate ®) fungicide at the rate of 5 g/4.5 1 of water, following an initial surface sterilization with 50% alcohol significantly reduced die back of nursery budding sprouts due to Botryodiplodia infection. A mean final bud-take of 62.0% on 3-month old budding sprouts was recorded for this treatment as compared with 28.0% in the conventional method. A procedural strategy is suggested to involve ringing twigs from which budwoods are to be collected 2 days before actual budding and cleaning the rootstocks and budwoods in benomyl solution (5 g/4.5 1 water) after an initial surface sterilization with 50% alcohol to improve brown budding efficiency.

Propagation of chestnut cultivars by grafting: Methods, rootstocks and plant quality

SummaryPropagation of chestnut has been studied to improve grafting success, but there are few results on the resistance of interspecific hybrid clones to ink disease of cultivars of Castanea sativa. This is an interesting combination in Europe for nut or nut and timber production. Five methods of grafting, nine Spanish hybrid rootstocks and the French CA15 Marigoule, different dates of grafting, height growth of grafted plants and short diameter up to four years, and compatibility between scion and rootstocks were studied. For five Spanish rootstocks, the results in the eighth and tenth year are presented. The best graft method was patch budding, although no significant differences were found between grafting methods since poor results were sometimes obtained with all methods. Grafting is most successful at the end of August and the beginning of September. We found low graft success in Spanish hybrid CHR-137. Severe incompatibility was shown early in the third year of growth with CA15 hybrid rootstock (C. crenata × C. sativa) and Spanish cultivars (C. sativa). Plant quality was very good two years after grafting, at 149 cm height for cleft graft and 156 cm for patch bud.

PILOT PROJECT TO CRYOPRESERVE DORMANT APPLE(Malus sp.) BUDS

Dormant buds of 64 apple accessions from the National Germplasm Repository (NGR), Geneva, NY were cryopreserved at the National Seed Storage Laboratory (NSSL), Fort Collins, Co. Initial tests after 1 mon, 1, 2, and 3 years of LN2 storage showed no decline in viability. Storage of 16 cultivars (1988/89 and 1989/90 dormant seasons) with a broad range of cold-hardiness characteristics has shown approx 45% viability by patch budding. Storage from dormant seasons of 1990/91 and 1991/92 included 48 cultivars selected for excellent cold-hardiness characteristics. With approx 85% initial viability of these cultivars, a more sensitive statistical analysis can be performed over years. Overall viability over storage duration and sampling years showed 32 had more than 80%, 55 had more than 50% and only 4 had less than 30%.

CRYOPRESERVATION OF DORMANT APPLE (Malus sp.) BUDS.

Cryopreservation of dormant buds has potential to provide back-up conservation of vegetatively propagated genetic resources for fruit crop species. This system may be useful where clonal integrity must be maintained and where it is desirable to rapidly recover plants with flowers for crossing purposes. In 1988, a pilot project involving the National Clonal Apple Repository at Geneva, NY and the National Seed Storage Laboratory, Fort Collins, CO, was initiated to test handling protocols as a prelude to establishing a cryopreservation backup system for apple genetic resources. Sufficient buds have been cryopreserved to permit viability evaluation after 1 month, 1, 2, 3, 4, 5, 10, 15, 20, and 25 years storage in liquid nitrogen vapor phase storage (-150 C]. Recovery of dormant buds collected 12/12/88 and 02/06/89 after one month in LN2 was 36% and 35%, respectively, for eight different taxa. After one year in LN2, recovery was 50% and 48% for the same taxa. The difference was attributed to improved handling during dehydration prior to patch budding for viability estimation. In 1990, recovery after 1 month in LN2 was 38% for six different cultivars. The response to controlled acclimation and desiccation for 15 taxa will be presented.

Influence of Gibberellic Acid on Early Patch Budding of Pecan Seedlings1

Abstract A lanolin - potassium gibberellin (GA3) mixture when applied to the trunks of pecan seedlings, beginning 7-10 days after emergence and continuing at 10-14 day intervals for a total of 4 treatments, resulted in sufficient trunk growth for successful patch budding to be accomplished by the end of the third month of growth.