Brij Lal Attri

Adventitious rooting in apple rootstock MM.106: Effects of arbuscular mycorrhizal fungi (AMF) and plant growth regulators

Summary To assess the efficacy of arbuscular mycorrhizal fungi (AMF) for improving the rooting and growth of hardwood cuttings of apple rootstock MM.106, three mycorrhizal species (Sclerocystis dussi, Glomus intraradices, and G. fasciculatum) were tested. Rootstock cuttings from each AMF inoculation treatment were then treated, or not treated, with the rooting hormone, indole 3-butyric acid (IBA), or a rooting inhibitor, cinnamic acid (CA) each at 2.5 g l–1. Cuttings that had not been inoculated with AMF or treated with either growth regulator served as controls. The results indicated that, after 90 d, cuttings inoculated with any of the three AMF alone, or in combination with 2.5 g l–1 IBA had significantly higher percentages of rooting and growth than the untreated controls. The combined application of AMF plus 2.5 g l–1 CA also improved the rooting percentage, which was significantly higher than in the untreated controls. Thus, the positive response to AMF inoculation was further improved when combined with 2.5 g l–1 IBA.

Performance of some new apple cultivars for yield and physico-chemical characters under mid-hill conditions of Uttarakhand

An experiment was conducted to evaluate the yield and physico-chemical performance of 18 apple cultivars. The highest fruit yield (46.11 kg/tree), fruit weight (217.33 g), fruit volume (231.67 cc), fruit length (6.98 cm) andfruit diameter (8.22 cm) was recorded in ‘Spur Type Red Delicious’. The lowest fruit yield (19.12 kg/tree) and fruitlength (4.33 cm) was recorded in ‘Chaubattia Anupam’; while, lowest average fruit weight (64.67 g), fruit volume (63.33 cc) and fruit diameter (5.32 cm) was observed in ‘Gloster’. The maximum TSS was recorded in ‘Skyline Supreme’ (14.73°B) and minimum was in ‘Chaubattia Princess’ (11.26°B). However, the highest titratable acidity was recorded in ‘Golden Delicious’ (0.66%) and lowest in ‘Chaubattia Princess’ (0.14%). The cultivar ‘Skyline Supreme’ possessing highest values for ascorbic acid (8.25 mg/100 g), reducing sugars (9.62%), total sugars(12.42%), total carotenoids (235.73 μg/100 g) and total anti-oxidant activity (41.95 mMTE/L) while ‘Prima’ exhibitedlowest values of ascorbic acid (3.92 mg/100 g) and total sugar contents (6.15%). The lowest values for reducingsugars (5.13%), total carotenoids (79.45 μg/100 g) and total anti-oxidant activity (30.66 mM TE/L) were recordedin ‘Gloster’, ‘Vermont Spur’ and ‘Stark Spur’, respectively. The cultivar ‘Golden Delicious’ is the most luminous(L*=84.86) and having the highest yellow colour (b*= 67.10) and hue angle (h° = 87.41), whereas ‘Chaubattia Anupam’ showed the highest red colour (a*= 54.15) and Chroma (C*= 67.53). From this investigation it can beinferred that the cultivar ‘Spur Type Red Delicious’ and ‘Skyline Supreme’ performed better in the region under prevailing climatic conditions.

Sharka in plums: Diagnostics and management

Sharka or plum pox is the most destructive disease of plums and other stone fruits belonging to genus Prunus, worldwide. The disease is incited by plum pox virus (PPV), a member of the genus Potyvirus and family Potyviridae. Timelydetection of PPV in fruit trees is necessary prior to embracing an appropriate management tool for containment of the disease to keep the crop loss sufficiently below the economic threshold level. PPV can be diagnosed by visual examination, particularly, during the period of active growth. Traditionally, cultural methods have been used to isolate and identify this dreaded pathogen. Alternatively, molecular detection techniques are also available which, can generate accurate results rapidly enough to be useful for disease management decisions. With the herald of new frontiers of science such as functional genomics and metabolomics, the development of more cost effective novel tools with exceptional sensitivity in real time is not a distant dream to be realized.