Effect of Some Botanical and Chemical preservatives against Termite Macrotermes bellicosus Smeath in Preserving Some Sudanese Timbers

Abstract

Effect of Some Botanical and Chemical preservatives against Termite Macrotermes bellicosus (Smeath.) in Preserving Some Sudanese Timbers

Neem Seed Kernel Oil (NSKO), Neem Seed Kernel Powder (NSKP) and boric acid (BA) were examined to test their effects on preserving wood of some valuable species against dry wood termites. Three locations representing different ecological zones of the Sudan were selected for the Study. These are; Berber (Northern Sudan), Shambat (Central Sudan), and Sinja (South-central Sudan). Two trials were carried out. First, field trial. In this experiment wood blocks from A. seyal, E. microthica, and C. africana of 5x5x30cm dimensions treated with NSKO, NSKP and BA and controlled untreated blocks were laid in a grave yard. Wood loss was determined at intervals for one year. Second experiment was laboratory test. The aim of this experiment is to investigate termite behavior while attacking the wood. A number of treated and untreated blocks of 5X5X5 cm dimensions were kept on glass gars size 15X15X20 cm. These gars were filled with termites nest individuals, and then put on a dark and conditioned room (28~32 C, and 80~90% MC).

In the field experiment results showed that chemical and botanical preservatives significantly reduced termite attack and weight loss. Botanicals used at this experiment keep treated blocks free from termites attack. The weight loss recorded at site No.1 (0.5 g) to C.africana treated with NSKO,(1 g) to A.seyal samples treated with NSKO,(1.1 g) to A.seyal samples treated with NSKP, and (1.3 g) to C.africana samples treated with NSKP, as a minimum weight loss reduction. at site No.2 weight loss recorded (0.8 g) to A.seyal samples treated with NSKP, (0.9 g) to E.microthica samples treated with NSKP, (2.9 g) to E.microthica samples treated with NSKO, (3.2 g) to C.africana samples treated with NSKO, (4.3 g) to C.africana samples treated with NSKO, (5.3 g) to E.microthica samples treated with NSKO, and (5.5 g) to E.microthica samples treated with NSKO, as a minimum weight loss reduction. And at site No-3 weight loss recorded (6.4 g) to E.microthica samples treated with NSKP as a minimum weight loss reduction.

On the other hand Chemical preservative used in these experiments was also control the termite's damage at the three graveyard areas. At site No-1 weight loss recorded (1.9 g) to C.africana treated with BA, (2.9 g) to C.africana treated with BA, and (5.3 g) to A.seyal samples treated with BA as a minimum weight loss reduction. At site No-2 weight loss recorded (.9 g) to E.microthica samples treated with BA, (1.4 g) to E.microthica samples treated with BA, (1.46 g) to E.microthica samples treated with BA, (1.5 g) to C.africana samples treated with BA, (2.4 g) to A.seyal samples treated with BA, and (2.8 g) to C.africana samples treated with BA, as a minimum weight loss reduction. And at the site No-3 weight loss recorded (6.7 g) to E.microthica samples treated with BA, and (11.22 g) to E.microthica samples treated with BA, as a minimum weight loss reduction.

For the behavior experiment results showed that the treated samples of (NSKO, and NSKP) was either sufficiently toxic and/or repellent to prevent termites feeding, termites mortality reached 100% in the third week to glass gars filled with samples treated with NSKO,95% to NSKP,85% to BA.

Termites attack was increased at the period from August - November during the rainy season There were no significant differences between the concentration used at (BA), and (NSKP), but concentration of 10% of (NSKO) at Shambat and Singa site is more effective.

The length of protection time is yet to be ascertained from record of service life time according to Findlay 1985 classified the three species used in this study A.seyal was moderately durable with no expected life of the test stakes in field, E.microthica was durable with 5-10 years as an expected on test stakes in field, and C.africana was durable with 5-10 years as an expected on test stakes in field.

M.bellicosus (smeath) was common in the south and west, but reaches further north along the banks of the Nile. It was distributed commonly at the east bank of the Blue Nile increased at Eljazair and Abujaily forest mainly.