Journal of Horticultural Sciences

B. Padmakar ¹, C. Kanupriya ², P. Madhavi Latha ², C. Vasugi ², M. R. Dinesh ², D. Sailaja ³, C. Aswath ²

Affiliations
1 Center for Biotechnology, JNTU, Hyderabad, Telangana, IN
2 ICAR-Indian Institute of Horticultural Research, Hesaraghatta Lake Post, Bengaluru - 560089, Karnataka, IN
3 Department of Biotechnology, GRIET, Hyderabad, Telangana, IN

Abstract

The present research focuses mainly on molecular mining and morphological evaluation of guava genome within a full-sib population and, thereby, mapping of quantitative trait loci related to fruit quality traits, viz., seed strength (hardness/softness) and average fruit weight. Linkage maps were enriched for both parental lines, 'Kamsari' and 'Purple Local' using a set of 60 RAPD markers following the pseudo-testcross strategy on a panel of 94 progeny. A total of 480 scorable markers were identified, of which 131 were specific to 'kamsari' and 28 to 'Purple Local', segregating as test cross markers, and, 321 showing intercross pattern common to both. 'Kamsari' spanned a total length of 1959.1cM with average marker interval distance of 3.93cM, while 'Purple Local' spanned a length of 1537.9cM with average marker interval distance of 3.29cM, by forming 11 linkage groups. Estimated genome length observed was 93.02% and 92.77% in 'Kamsari' and 'Purple Local', respectively. Composite Interval Mapping (CIM) was computed at significance of 0.05 and LOD threshold greater than 3.0, which led to detection of one major QTL for the trait of average fruit weight, and, four QTLs for the trait of seed strength (hardness/softness). Of these, two were major and two minor QTLs. Our study provides molecular mapping information on marker-assisted selection for improvement of guava in a breeding program.

Keywords

Composite Interval Mapping, Guava, Linkage Map, Pseudo-Testcross, Quantitative Trait Loci (QTL).

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M. R. Dinesh ¹, C. Vasugi ¹, R. Venugopalan ¹

Affiliations
1 ICAR-Indian Institute of Horticultural Research, Hesarghatta Lake Post, Bengaluru - 560089, IN

Abstract

Mango is a perennial and highly heterozygous plant. Therefore, it takes a long time to breed a variety in this crop. Information on genetic variability among cultivars and hybrids helps plan meaningful crop improvement programmes. Due to the high heterozygosity, complexity of its flowers and poor fruit-set, the progeny population that can be raised from a cross is very meagre. Hence, there is a need to choose parents that have good fruit-set and show genetic divergence. It would also be interesting to establish if the hybrids generated are truly open-pollinated progenies, or arise from controlled crossing. Basic information thus obtained would help chalk out a potentially successful breeding programme. A study in this direction was carried out by using morphological characters of twelve hybrids and their respective parents. Cluster analysis indicated a relationship between the parents and hybrids. Two major clusters were observed from the clustering pattern. In the first cluster, varieties Dashehari, Banganapalli, Manjeera, Sindhu, Janardhan Pasand, Ratna, Rumani, Amrapali, Neelgoa and Alphonso grouped together. The second cluster consisted of vars. Arka Aruna, Neelum, Arka Puneet, Neeleshan, Mulgoa, Mallika, Arka Anmol and Arka Neelkiran. The hybrid, Sindhu was observed to be genetically closer to Ratna than to Alphonso. The sub-clustering pattern also showed a close relationship between parents and their hybrids. The hybrid, Arka Anmol, was found to distantly placed from the centre (8.54), as also the hybrid, Arka Neelkiran (7.05). 'Sindhu' was also found to be closer to the centre (1.55).

Keywords

Breeding, Characterization, Cluster Analysis, Heterozygosity, Genetic Variability.

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M. V. Naga Chaithanya ¹, M. R. Dinesh ², C. Vasugi ², D. C. Lakshmana Reddy ¹, D. Sailaja ³, C. Aswath ¹

Affiliations
1 Division of Biotechnology, ICAR- Indian Institute of Horticultural Research, Hesaraghatta Lake Post, Bengaluru-560 089, IN
2 Division of Fruit Crops, ICAR- Indian Institute of Horticultural Research, Hesaraghatta Lake Post, Bengaluru-560 089, IN
3 Department of Biotechnology, Gokaraju Rangaraju Institute of Engineering and Technology, Hyderabad-500090, IN

Abstract

Although the varietal diversity is fairly rich in guava, most varieties lack one or more desirable characters. Hence, attempts were made for improving specific traits, viz., attractive pink pulp colour, soft seeds, medium fruit size, high TSS and high ascorbic acid. Genetic diversity analysis is a prerequisite for identifying potential parents in breeding programs and germplasm conservation. Molecular characterization helps discriminate closely-related genotypes, as, this technique is unaffected by environment, rendering it more reliable. In this study, 48 polymorphic SSRs screened from a total of 115 SSR markers were used for analyzing marker segregation in 72 guava accessions. Statistical analysis was done using IDENTITY1.0 and CERVUS 3.0 software. Cluster analysis was done with DARwin 5.0 software, using Wards Minimum Variance method, and weighted group neighbour joining method, to check reliability of grouping among clusters. The trend in grouping was found to be similar in both methods. Dendrograms generated showed that the hybrids clustered with their parents; exotic collections fell into two different sub-groups based on productivity; the wild species formed one group; and Navalar cultivars from Dharwad clustered together, reflecting similar origin.

Keywords

Guava, Genetic Diversity, Dendrogram, Simple Sequence Repeats.

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C. Vasugi ¹, M. R. Dinesh ¹, R. Chithiraichelvan ¹

Affiliations
1 Division of Fruit Crops, Indian Institute of Horticultural Research, Hessaraghatta Lake Post, Bangalore - 560 089, IN

Abstract

Mango is an important fruit crop grown extensively in India. An enormous diversity is seen in its flavour, taste and fruit form unique to particular regions of India. A large diversity for unique pickling types, called 'Appemidi' (tender mangoes), is seen in Uttara Kannada district of Karnataka. With rapid deforestation in several of these areas, surveys were conducted to collect and conserve these unique types. This resulted in collection of 33 unique accessions which have been conserved in the Institute's field gene bank. On evaluation of tender fruit, accessions 'Chansi Appe', 'Dodderi Jeerige', 'Mani Bhatta Appe', 'Gorana Appe', 'Isagoor Appe', 'Malange', 'Gurumurthy Appe' and 'Kashimidi' were found to possess good traits for tender, whole-fruit pickling.

Keywords

Mango, Evaluation, Appemidi, Pickling, Conservation.

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M. R. Dinesh ¹, C. Vasugi ¹

Affiliations
1 Division of Fruit Crops, Indian Institute of Horticultural Research, Hessarghatta Bangalore-560089, IN

Abstract

Guava (Psidium guajava L; Myrtaceae) is an important fruit crop of India. High heterozygosity and frequent cross pollination resulted in the present day variability in seedling populations from which promising genotypes have been selected. As of now, there are about 160 cultivars available in India, among which 'Allahabad Safeda' and 'Sardar' varieties are widely cultivated. Crop improvement work attempted in India resulted in release of several superior selections / hybrids. Also, interspecific hybrids resistant to guava wilt were developed at CISH, Lucknow which are graft compatible with commercial varieties of P. guajava. The use of new biotechnological tools like DNA fingerprinting to study the extent of genetic variation among cultivars, rapid multiplication through in vitro shoot-tip culture needs to be employed extensively. Attempts need to be made to spot genetic markers for wilt resistance to improve efficiency in developing wilt resistant clones and ischolar_mainstocks. Survey to identify superior genotypes with Allahabad Safeda traits and high density planting characters like early bearing, compact plant type, favourable response to pruning, good branch angle to minimize branch breakage even under heavy bearing, and, with a high fruit : shoot ratio need to be paid due attention. Work on aneuploidy breeding, development of autotetraploids and in vitro genetic manipulation of somatic cells needs to be intensified.

Keywords

Guava, Improvement, Varieties/Hybrids, Psidium sp.

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C. Vasugi ¹, K. Sekar ², M. R. Dinesh ¹, E. R. Suresh ¹

Affiliations
1 Indian Institute of Horticultural Research, Hessaraghatta Lake Post, Bangalore-560089, IN
2 Department of Horticulture, Annamalai University, Annamalai Nagar, Tamil Nadu, IN

Abstract

Studies conducted to evaluate the suitability of nineteen unique mango accessions for preparation of tender whole mango pickles revealed that these varieties were characterized by their acidic taste and rich raw mango flavour, which are most prefered for pickle production. The physical and quality parameters viz. fruit shape, weight, raw mango flavour, firmness, titrable acidity, latex flow, pH, dry matter and vitamin C which are important in pickle quality, showed wide variations among different varieties. Based on the sensory evaluation of whole immature green mango pickle prepared by standard fermentation and curing method, the accessions viz., Kashimidi, Isagoor Appe, Malange, Appemidi, Dantimamidi and Jeerige were considered to be most suitable for preparation of tender mango pickles.

Keywords

Germplasm, Raw Tender Mango, Pickle, Variability, Sensory Evaluation, Unique Accession.

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P. Venkata Rami Reddy ¹, C. Vasugi ¹

Affiliations
1 Division of Plant Genetic Resources, Indian Institute of Horticultural Research, Hessaraghatta Lake Post, Bangalore-560089, IN

Abstract

Five wild species of Psidium viz., Psidium cattleianum lucidum, P. chinensis, P. friedrichsthalianum, P. molle and P. quadrangularis were evaluated for resistance to fruit fly [Bactrocera dorsalis (Hendel)] and tea mosquito bug (TMB) [Helopeltis antonii (Sign.)], during 2002-04. Significant variations were recorded among species in their reaction to pests. Two species viz., P. chinensis and P. quadrangularis were resistant to fruit fly (<10% fruit damage) while P. quadrangularis was immune. Psidium. molle and P. cattleianum were resistant to tea mosquito bug. Pest incidence was correlated with fruit biochemical components viz., total soluble solids (TSS), total sugars, vitamin C and acidity. The TSS and total sugars were positively correlated with fruit fly infestation while acidity was negatively correlated. The TMB incidence did not exhibit significant correlation with any of these parameters.

Keywords

Guava, Psidium Species, Resistance, Fruit Fly, Tea Mosquito Bug.

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