RESPON ANATOMIS BATANG DAN FISIOLOGIS TANAMAN KANGKUNG DARAT (Ipomoea reptans Poir.) TERHADAP TIMBAL

VIDYA HANUM AYUNINGTYAS, Dr. E. Suharyanto, M.Sc.

2014 | Skripsi | BIOLOGI

Timbal (Pb) merupakan salah satu logam berat yang dihasilkan oleh industri, khususnya industri baterai, alat listrik, dan percetakan. Pb juga digunakan pada bensin, cat dan pestisida. Pb merupakan pencemar di semua lingkungan (multimedia pollutant) dan sumber utama pencemaran tanah. Tumbuhan kangkung darat (Ipomoea reptans Poir.) diketahui dapat menyerap logam berat melalui akar. Tujuan penelitian ini untuk mengetahui respon anatomis, fisiologis, dan morfologis Ipomoea reptans Poir. terhadap berbagai logam Pb. Percobaan dilakukan dengan perlakuan Pb(NO3)2 konsentrasi 60, 80, 100, dan 120 ppm beserta kontrol negatif pada tanaman yang berumur 10 hari perkecambahan. Parameter yang diamati : diameter batang, tebal epidermis, tebal korteks, tebal trakea, tebal stele, diameter rongga empulur, kadar klorofil a, klorofil b, klorofil total, kadar Pb pada akar, batang, daun, tinggi tanaman, jumlah daun, dan rasio panjang dan lebar daun. Data yang diperoleh dianalisis dengan ANOVA dan dilanjutkan dengan uji DMRT dengan taraf signifikan 5%. Hasil penelitian menunjukkan bahwa pemberian Pb 120 ppm menyebabkan penurunan diameter batang, tebal trakea, tebal korteks, tebal stele dan diameter rongga empulur. Sebaliknya, konsentrasi optimum Pb 120 ppm meningkatkan tebal epidermis. Perlakuan Pb dengan konsentrasi sampai dengan 120 ppm menurunkan kadar klorofil a, b, dan total. Logam Pb terakumulasi pada akar dalam jumlah sedikit pada pemberian Pb konsentrasi 60 dan 80 ppm. Logam Pb tidak mempengaruhi tinggi, jumlah daun, dan rasio panjang dan lebar daun tanaman. Dari hasil tersebut dapat disimpulkan bahwa logam Pb yang terserap dapat mempengaruhi ketebalan sel epidermis serta diameter batang, sel trakea, rongga empulur, jaringan korteks dan stele dan klorofil a, b, total batang I. reptans tetapi belum mampu mempengaruhi morfologi tanaman.

Lead (Pb) is a heavy metal which is widely used by human in some industries, especially batteries, power tools, and printing industries. It is also used in gasoline, paints and pesticides. This metal is an environmental pollutant (multimedia pollutant) and the main source of soil contamination Water spinach (Ipomoea reptans Poir.) are known to absorb heavy metals through their roots. The purpose of this study was to study the anatomical, physiological, and morphological responses of Ipomoea reptans Poir. to lead. Research was carried out by treating plants with Pb (NO3)2 60, 80, 100, and 120 ppm along with a negative control at 10 days old plant. Parameters observed were stem diameter, epidermis cells thickness, cortex thickness, trachea thickness, stele thickness, pith cavity diameter, levels of chlorophyll a, chlorophyll b, total chlorophyll, lead concentrations in the roots, stems, leaves, plant height, number of leaves, and ratio of the length and with. Data were analyzed by ANOVA followed by DMRT with 5% of significance level. The results showed that 120 ppm Pb affects the anatomical structure of the stem by reducing stem diameter, trachea cells diameter, cortex thickness, stele thickness and pith cavity diameter. Otherwise, 120 ppm of Pb increased epidermal cells thickness. Pb concentration up to 120 ppm reduced chlorophyll a, b, and total content. Pb was accumulated in small amounts in the roots plant treated with 60 and 80 ppm of Pb. Pb did not affect the height plant, number of leaves, and the ratio of the length and width of plant leaves. From these results it can be concluded that the adsorbed Pb can affect the epidermal cells thickness, diameter of stem, trachea, pith cavity, cortex and stele tissues. Pb affect chlorophyll a, b, c and total of I. reptans but has not been able to affect plant morphology.

Kata Kunci : Ipomoea reptans, timbal, anatomi, klorofil