Journal of Medicinal and Aromatic Plant Sciences 27 (2005) 39-42.

Chemical quality of berries from black pepper varieties grafted on Piper colubrinum

T. John Zachariah*, P.A. Mathew and P. Gobinath
Indian Institute of Spices Research, Marikkunnu, Calicut- 673012, Kerala, India. Received 7"' December, 2004
Abstract

Black pepper (Piper nigrum L.) is a major spice used in food and medicine and the raw material for extracting volatile. oil, oleoresin and piperine. Phytophthora foot rot is the major disease affecting pepper plant killing the entire vine. P. colubrinum Link, a related species is unaffected by this fungi. Grafting P.nigrum on P. colubrinum is one approach to safeguard the pepper from this disease. Using P. colubrinum as rootstock chemical qualities of pepper berries of important pepper varieties were evaluated, since volatile oil, oleoresin and piperine contribute towards its aroma, taste and pungency. The study included the components of the essential oil such as pinene, sabinene, myrcene, limonene, linalool, terpinene-4-ol, a- terpineol and P-caryophyllene also. Grafting has not influenced the chemical quality of berries.

Key words : P. nigrum, P. colubrinum, grafting, rootstock, scion, piperine, caryophyllene, sabinene.

Introduction Black pepper (Piper nigrum L.) is a major
economically important spice globally used in food and medicine. Foot rot caused by Phytophthora capsici Leonian is the major production constraint in black pepper growing. Though chemical and biological control methods are in vogue, resistant rootstock is one approach adopted in many crops to overcome such problems. Piper colubrinum Link is a wild relative of black pepper resistant to the above pathogen and has been tested in Brazil [1] and Indonesia [11].
Similar attempts have been made at Indian Institute of Spices Research, Kerala, India [6] and research is in progress.
The quality of black pepper berries is dependent on the components of volatile oil, oleoresin and piperine [11]. The aroma and flavour of pepper is determined by the composition of its steam volatile oil, which comprises mainly of monoterpene hydrocarbons together with smaller amounts of sesquiterpene hydrocarbons. Oxygenated compounds, though minor, play an important role in deciding the organoleptic properties

of this spice and its oleoresin [9]. Pepper also contains about 9% alkaloids (mostly piperine and analogues), about 11 % protein and small amounts of minerals. The therapeutic properties of pepper oil are due to these components. However, the content and the intrinsic quality of oil, oleoresin and related principles is dependent on various factors such as variety, geographical origin, age, quality of the materials used and the processing procedure employed [3,9,12,13,]. Nevertheless, a need was felt to study the influence of P. colubrinum rootstock on berry quality components to assess its utility. Such studies have been carried out in Malaysia and no rootstock effect was detected [13]. Therefore, this study was carried out to assess the effect of Piper colubrinum as a rootstock on the chemical quality profile in different pepper cultivars under Indian conditions.

Materials and methods
Berries collected from five-year-old grafts and nongrafts of Panniyur-I, II, III, IV, V, Malligesara, Pournami, Sreekara, Poonjaranmunda, Kuthiravalli, Panniyur culture and Balankotta were used for the study. The

* E-mail: zacjontj@yahoo.co.uk

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