Determination of maturity indices in mandarin orange

Abstract

Abstract : The experiment was conducted at the Regional Horticulture Research Station (RHRS), Akbarpur, Moulvibazar during 2010 to standardize the optimum harvesting time of three genotypes of mandarin based on better physical, chemical and qualitative characteristics of fruits. The mandarin genotypes namely CR-Mou 007, CR-Mou 008 and BARI Komala-1 were used in the experiment and the fruits were harvested at 15 days interval starting from 1st October 2010. The initial sign of mandarin maturity was a change in ’ peel colour, from green to orange. The fruit colour of CR-Mou 007 (Nagpuri), CR- Mou 008 (Khasi) and BARI Komala-1 (Khasi) changed gradually from deep green (01 October) to orange colour (01 December) with the delay of harvesting. The heaviest fruit (142.50 g) was found in BARI Komala-1 harvested at 01 December, which was statistically identical with the fruit of CR-Mou 008 harvested from 16 November to 01 December. Maximum juice content (52.07 %), total sugar (7.47 %), reducing sugar (3.15%) and sugar acid ratio (11.20) was observed in BARI Komala-1 when harvested at 01 December. The mandarin was sour at early harvesting at 01 October and turned to sweet in 01 November and very sweet in 16 November and 01 December. The highest sugar acid ratio (11.20) was recorded in BARI Komala-1 when harvested at 01 December. The mandarin fruits possessed better quality in respect of physicochemical and qualitative characteristics if harvest during November to 1st week of December when fruit age ranged from 245 to 260 days from fruit set.