HUBUNGAN ANTARA KERAPATAN POPULASI KEPIK RENDA, Diconocoris hewetti (Dist) (HEMIPTERA : TINGIDAE) DAN KEHILANGAN HASIL PADA TANAMAN LADA

ABSTRAK Kepik renda, Diconocoris hewetti (Dist) (Hemiptera : Tingidae) merupakan salah satu hama yang menyerang tanaman lada di Indonesia. Hama ini mengisap bunga lada, dan dapat menggagalkan pembuahan. Tujuan penelitian adalah untuk mengetahui hubungan antara kerapatan populasi D. hewetti dan kerusakan bunga serta pembentukan buah pada berbagai fase bunga. Penelitian dilaksanakan di rumah kaca dan kebun percobaan Petaling BPTP Kepulauan Bangka Belitung pada musim hujan (Nopember 2003 – Pebruari 2004). Penelitian rumah kaca menggunakan lada perdu varietas LDL umur ± 1 tahun. Kerapatan populasi nimfa instar 5 dan imago masing-masing 0,1 dan 2 per tandan bunga masing-masing pada 3 fase bunga. Periode mengisap bunga selama 24 jam. Rancangan percobaan yang digunakan adalah acak lengkap dengan pola faktorial dan diulang 5 kali. Percobaan lapangan menggunakan varietas LDL, umur ± 6 tahun. Populasi imago 0, 1, 2, 3, dan 4 per 4 tandan bunga masing-masing pada 3 fase bunga. Periode mengisap bunga selama 72 jam. Untuk nimfa menggunakan kerapatan populasi 0, 1, 2, dan 3 per tandan. Pemaparan serangga selama 24 jam. Rancangan percobaan untuk nimfa menggunakan acak kelompok dengan pola faktorial dan diulang 5 kali, sedangkan untuk imago juga menggunakan rancangan acak kelompok dengan pola faktorial dan diulang 6 kali. Parameter yang diamati adalah persentase kerusakan bunga, buah terbentuk, buah yang tidak terbentuk dan kehilangan hasil. Hasil penelitian menunjukkan perbedaan yang nyata antara kerapatan populasi kepik renda dengan kerusakan bunga lada dan pembentukan buah. Pada kerapatan 2 ekor nimfa maupun imago menunjukkan kerusakan bunga dan kehilangan hasil yang paling tinggi. Kerusakan bunga dan pembentukan buah akibat serangan imago dan nimfa tidak menunjukkan perbedaan yang nyata. Tingkat kerusakan bunga di rumah kaca antara 67,00–87,89%, sedangkan di lapangan antara 61,10–85,30%, disebabkan oleh imago kepik renda, dan 71,00-93,30% oleh nimfa. Kehilangan hasil di rumah kaca antara 55,07–83,04%, sedangkan di lapangan antara 35,30–82,89%, disebabkan oleh imago, sedangkan oleh nimfa berkisar antara 73,24–89,05%. Tingkat kerusakan bunga lebih tinggi pada fase 1 dan 2 dibandingkan dengan fase 3. Hasil penelitian ini memberikan indikasi bahwa serangan oleh satu ekor nimfa maupun imago kepik renda mengakibatkan kerusakan bunga minimal 61,10% dan kehilangan hasil minimal 35,30%. Kata kunci : Lada, Piper nigrum, hama, Diconocoris hewetti, kerusakan bunga, kehilangan hasil ABSTRACT Relationship between the population densities of blossom sucking lace bug Diconocoris hewetti (Dist) (Hemiptera; Tingidae) and yield losses on pepper plantation Blossom sucking lace bug, Diconocoris hewetti (Dist) (Hemiptera; Tingidae) is one of the pest insect attacking pepper in Indonesia. This pest insect sucks pepper blossom liquid and disturb fruit formation. The objective of this experiment was to find out the relationship between the population densities of blossom sucking lace bug, D. hewetti and flower damage, number of fruits formed and yield losses of pepper at various flower phases. These studies were conducted in a green house and pepper plantation in the Institute of Assessment Agricultural Technology, Bangka Belitung Island during rainy season (November 2003 to February 2004). The green house research used bushy pepper more or less 1 year old. The lace bug of the last instar or 5 th instar nymph and adult were used at population density : 0, 1 and 2 insects/bunch in 3 blossom phases respectively. Feeding period of lace bug was 24 hours. Design of this experiment was completely randomized with factorial design and 5 replications. Field study used LDL pepper variety with aged ± 6 years. The population densities of adult lace bug were: 0, 1, 2, 3 and 4 per 4 bunches on 3 types of pepper blossom phases respectively. Feeding period of lace bug was 72 hours. Field study also used last instar nymph with population density : 0, 1, 2 and 3/bunch. Feeding period was 24 hours. Randomized block design with factorial and 5 replications were used on instar nymph, while on the adult stadium randomized block design with factorial and 6 replications were also used. The intensity of flower damage, fruits formed, fruits unformed and yield losses were counted. The result revealed that the number of fruits formed and yield losses were significantly different among population density of lace bug. The population densities of two lace bug caused higher flower damage and yield losses than other population densities. Flowers damage, fruits formation and yield losses caused by nymph and adult were not significantly different. The level of flower damage in green house observation was between 67.00 – 87.89%, while in the field was between 61.10 – 85.30% caused by adult, and 71.00 – 93.30% caused by nymph. Yield loss of pepper was 55.07 – 83.04% in the green house, while the yield losses in the field was 35.30 – 82.89% due to the attack of adult. Yield loss caused by nymph was 73.24 – 89.05%. The level of flower damage on phases 1 and 2 were higher than the flower damage of phase 3. This research indicated that the attack of one adult or one nymph of lace bug, D. hewetti caused flower damage minimum 61.10% and yield loss minimum 35.30%. Key words : Pepper, Piper nigrum, pest insect, Diconocoris hewetti, flower damage, yield loss