ECONOMIC IMPORTANCE OF INSECTS ON REGROWTHS OF ESTABLISHED ALFALFA FIELDS IN ONTARIO

1983 ◽  
Vol 115 (7) ◽  
pp. 859-868 ◽  
Author(s):  
S. M. Smith ◽  
C. R. Ellis

AbstractDamage caused by Empoasca fabae (Harris) and Philaenus spumarius (L.), caged on second and third alfalfa harvests, was additive. Numbers of E. fabae were linearly correlated negatively with plant height, leaf area, and percentage protein, and positively with percentage chlorosis. Perceptible stunting and yellowing occurred with mean infestations per stem of 0.09 E. fabae and 0.6 P. spumarius nymphs. P. spumarius adults reduced plant height only at infestations of 0.3/stem, while 0.6 nymph/stem also reduced dry weight. E. fabae reduced protein at 0.11/stem and dry weight and leaf area at higher populations of 0.17/stem. None of these parameters was affected on subsequent regrowths. Lygus lineolaris (P. de B.) could not be maintained on pre-bloom alfalfa and was not considered a pest. Adelphocoris lineolatus (Goeze) reduced protein at levels of 0.01 bug/stem and dry weight at 0.06 bug/stem but results were confounded by high mortality. Field populations of all these species were reduced by the second cutting but redeveloped on the regrowth. Although applications of dimethoate (200 g AI/ha) and dimethoate (200 g AI/ha) plus endosulphan (280 g AI/ha) were effective in reducing populations of E. fabae, Acyrthosiphon pisum (Harris), A. lineolatus, and Hypera postica (Gyllenhal), insecticides were cost-effective on only one field. This field had 1.9 E. fabae/sweep and a 3% loss in protein resulted. Plant height, density, dry weight, protein content, and overwintering survival were not significantly affected at harvest in other fields. With the exception of E. fabae, the sum of the maximum field populations, each expressed as a fraction of its threshold, did not reach 50% of an economic threshold.

2020 ◽  
Vol 11 (1) ◽  
pp. 25
Author(s):  
AHMAD TAOFIK ◽  
SOFIYA HASANI ◽  
AYU CAHYANINGTYAS ◽  
BUDY FRASETYA

The paitan plant contains allelopathic compounds for other plants so that the utilize of paitan plant as a source of liquid organic fertilizer (LOF) has not been widely applied. This research aimed to study the interaction between LOF dosage and appropriate application method of LOF to increase the growth of kailan plants. The research conducted at experimental garden of UIN Bandung from June-August 2016. The experimental design was a completely randomized design with two factors and replicated four times. The first factor was application methods (A), i.e. a1=direct application to the soil, and a2= spraying. The second factor was LOF dosage (T), i.e. t0: 0 ml plant-1, t1: 20 ml plant-1, t2: 40 ml plant-1, t3: 60 ml plant-1, t4: 80 ml plant-1. The growth parameters observed i.e. plant height (14, 21, 28, 35 and 42 Day after Transplanting (DAT)), leaf area 42 DAT, plant dry weight 42 DAT, and plant fresh weight 42 DAT. The data then analyzed with analysis of variance at a significant level of 5%. If the analysis of variance was significant, the Duncan multiple range test was used at α=5%. The research results showed there was no interaction between method of application with a various dosage of paitan LOF to all of the growth parameters. The application paitan LOF showed similar growth in terms of plant height, leaf area, plant dry, and plant fresh weight. The application method of paitan LOF direct to the soil or spraying to leaves can not increase kailan plant growth.


2020 ◽  
Vol 10 (4) ◽  
pp. 159
Author(s):  
. EMMYZAR

<p>Tanaman nilam tumbuh dan berproduksi dengan baik pada daerah dengan curah hujan relatif tinggi dan merata sepanjang tahun. Tanaman dalam kondisi kekurangan air terus menerus akan mengalami strcs air dan berpengaruh terhadap proses fisiologis, menurunkan permukaan trans- pirasi, luas daun menurun, dan mempercepat dcfiidrasi protoplasma. Penelitian pengaruh ketersediaan air terhadap petumbuhan dan produksi 2 (dua) klon nilam dilakukan di rumah kaca Instalasi Penelitian Cimanggu, Balittro Bogor mulai bulan Nopember 1999 sampai dengan Mei 2000. Penelitian ini betujuan untuk mengetahui pengaruh ketersediaan air terhadap partumbuhan dan produksi dua klon nilam (klon Sidikalang dan klon Situak) sekaligus diamati pengaruhnya terhadap kadar dan kualitas minyak nilam (rendemen, warna dan kandungan patchouly alkohol). Percobaan dilakukan dalam polibag menggunakan tanah kering jenis latosol Cimanggu Bogor yang diaduk dengan pupuk kandang sapi (3:1) sebanyak 10 kg/polibag disusun menggunakan rancangan factorial (dua faktor) dalam rancangan acak lengkap (RAL), diulang 3 kali. Ukuran plot 8 polibag/ perlakuan. Faktor pertama : klon nilam terdiri dari 2 jenis (K) yaitu : Kl = klon Sidikalang dan K2 = klon Situak. Faktor kedua: tingkat ketersediaan air (A) 4 taraf yaitu Al = 25% kapasitas lapang, A2 = 50% kapasitas lapang, A3 = 75% kapasitas lapang, dan A4 = 100 % kapasitas lapang. Peubah yang diamati meliputi persentase tumbuh tunas, tinggi tanaman, luas daun, bobot daun basah dan bobot daun kering, kadar minyak digambarkan dari rendemen dan kualitas minyak (wana dan kandungan patchouly alkohol). Hasil penelitian menunjukkan bahwa untuk jumlah tunas tidak ada interaksi antara tingkat ketersediaan air dan klon yang diuji, tetapi untuk jumlah daun ada interaksi. Tingkat pemberian air 75% kapasitas lapang (KL) secara keseluruhan memberikan pertumbuhan optimum bagi kedua klon, kecuali untuk parameter jumlah daun. Pada klon Situak. tingkat pemberian air 100% KL yang memberikan jumlah daun terbanyak. Perlakuan ketersediaan air 100% KL pada klon Sidikalang memberikan bobot daun kering tetinggi dibanding perlakuan lainnya, sedang untuk klon Situak, ketersediaan air pada taraf 75% KL memberikan bobot daun kering tetinggi. Rendemen minyak klon Situak dengan tingkat ketersediaan air 25% KL tertinggi (4.0%) dengan wana minyak kuning muda tcrang, diikuti tingkat 50% KL (3.0%) dengan wana minyak kusam/kemh. Kandungan patchouly alkohol klon Situak rata-rata (30%) lebih baik daripada klon Sidikalang, diperoleh dari perlakuan ketersediaan air 25% KL. Dapat disimpulkan bahwa untuk memperoleh petumbuhan dan produksi yang tinggi, ketersediaan air dalam tanah diperlukan antara 75 - 100% KL. Namun, untuk mendapatkan kandungan patchouly alkohol tinggi ketersediaan air yang dibutuhkan lebih rendah yaitu 25 % - 50%) KL.</p><p>Kata kunci: Nilam, Pogostemon cablin, ketersediaan air, petumbuhan, produksi</p><p> </p><p><strong>ABSTRACT</strong></p><p><strong>The effect of water availability the growth and production of two patchouly clones </strong></p><p>Patchouly plant grows and produces very well in the area with high and everly rain fall through the year. Plants with continuous shortage of water would face water stress and affect physiologis process, transpiration surface, leaf area and protoplasmic dehydration. Several levels of water needs were tested in this experiment, which was carried out in a glass house of Cimanggu Installation, Indonesian Spice and Medicinal Crops Research Institute, Bogor, rom November 1999 to May 2000. The objective was to find out the effect of water availability on two clones of patchouly growth, production and oil content (rendement, colour and patchouly alcohol). The experiment was conducted in polybags using Cimanggu Latosol soil mixed with cow dung (3:1), 10 kg/polybag, arranged in a factorially completely random design with 3 replications. Plot size was 8 polybag/treatment. The first factor was two clones of patchouly : K, = Sidikalang and K2 = Situak. The second factor was 4 levels of water availability: 2J% (A,), 50% (A2). 75% (A,), and 100% (A,) ield capacity (FC). Variables observed were percentage of shoot growth, plant height, leaf area, fresh weight and dry weight, oil content (rendement, colour and patchouly alcohol). The result showed that there was no interaction between the two factors for number of shoots. Clone of Sidikalang had higher plant height than that of Situak. The water availability of 75% (FC) gave optimum growth for the two clones, except the number of leaves. For Situak the water avaibility of 100% (FC) gave the highest number of leaves. For Sidikalang the water availability of 100% gave the highest dry weight of leaves. Oil rendement for Situak with 25% FC was the highest (4.0) with bright yellow colour. The content of patchouly alcohol for Situak was higher than that of Sidikalang (30%). Therefore, it can be concluded that to obtain the optimum growth and the higest production it needed 75 - 100% (FC) water availability, while for high patchouly alcohol content, it needed buzer the water availability, i.e. 25-50% (FC).</p><p>Key words: Patchouli, Pogostemon cablin, water level, growth, production</p>


2018 ◽  
Vol 98 (6) ◽  
pp. 1321-1330
Author(s):  
Jaimin S. Patel ◽  
Leora Radetsky ◽  
Mark S. Rea

Sweet basil (Ocimum basilicum L.) is primarily used for culinary purposes, but it is also used in the fragrance and medicinal industries. In the last few years, global sweet basil production has been significantly impacted by downy mildew caused by Peronospora belbahrii Thines. Nighttime exposure to red light has been shown to inhibit sporulation of P. belbahrii. The objective of this study was to determine if nighttime exposure to red light from light-emitting diodes (λmax = 625 nm) could increase plant growth (plant height and leaf size) and yield (number and weight of leaves) in basil plants. In two sets of greenhouse experiments, red light was applied at a photosynthetic photon flux density of 60 μmol m−2 s−1 during the otherwise dark night for 10 h (from 2000 to 0600). The results demonstrate that exposure to red light at night can increase the number of basil leaves per plant, plant height, leaf size (length and width), and leaf fresh and dry weight compared with plants in darkness at night. The addition of incremental red light at night has the potential to be cost-effective for fresh organic basil production in controlled environments.


1994 ◽  
Vol 8 (1) ◽  
pp. 154-158 ◽  
Author(s):  
William E. Haigler ◽  
Billy J. Gossett ◽  
James R. Harris ◽  
Joe E. Toler

The growth, development, and reproductive potential of several populations of organic arsenical-susceptible (S) and -resistant (R) common cocklebur biotypes were compared under noncompetitive field conditions. Plant height, leaf area, aboveground dry weights, and relative growth rate (RGR) were measured periodically during the growing season. Days to flowering, bur dry weight, and number of burs per plant were also recorded. Arsenical S- and R-biotypes were similar in all measured parameters of growth, development, and reproductive potential. Populations within each biotype varied occasionally in plant height, leaf area, aboveground dry weights, and reproductive potential.


Pastura ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 33
Author(s):  
Roni N.G.K. ◽  
S.A. Lindawati

The productivity of forage depends on the availability of nutrients in the soil where it is grown, so fertilization to replace harvested produce is absolutely necessary. This study aims to study the response of gamal and indigofera forage on application of inorganic and organic fertilizers. Research using a completely randomized design factorial pattern of two factors, the first factor is the type of plant (G = Gamal; I = Indigofera) and the second factor is the type of fertilizer (T = without Fertilizer; A = Inorganic fertilizer NPK; K = commercial organic fertilizer; O = conventional organic fertilizer; B = bioorganic fertilizer), repeated 4 times so that it consists of 40 experimental units. The variables observed were plant height, number of leaves, stem diameter, leaf dry weight, stem dry weight, total dry weight of leaves, ratio of dry weight of leaves/stems and leaf area per pot. The results showed that there was no interaction between plant species and types of fertilizer in influencing the response of gamal and indigofera plants. Plant species have a significant effect on stem diameter, while fertilizer types have a significant effect on plant height, leaf dry weight, total dry weight of leaves and leaf area per pot. Based on the results of the study it can be concluded that the response of gamal plants is similar to indigofera, all types of fertilizers can improve the response of plants and organic fertilizers produce the same crop response with inorganic fertilizers. Keywords: gamal, indigofera, inorganic fertilizer, organic fertilizer


1970 ◽  
Vol 34 (1) ◽  
pp. 67-73
Author(s):  
M SH Islam ◽  
MSU Bhuiya ◽  
AR Gomosta ◽  
AR Sarkar ◽  
MM Hussain

Pot experiments were conducted during T. aman 2001 and 2002 (wet season) at Bangladesh Rice Research Institute (BRRI) in net house. Hybrid variety Sonarbangla-1 and inbred modern variety BRRI dhan-31 were used in both the seasons and BRRI hybrid dhan-l was used in 2002. The main objective of the experiments was to compare the growth and yield behaviour of hybrid and inbred rice varieties under controlled condition. In 2001, BRRI dhan-3l had about 10-15% higher plant height, very similar tillers/plant, 15-25% higher leaf area at all days after transplanting (DAT) compared to Sonarbangla-1. Sonarbangla- 1 had about 40% higher dry matter production at 25 DAT but had very similar dry matter production at 50 and 75 DAT, 4-11% higher rooting depth at all DATs, about 22% higher root dry weight at 25 DAT, but 5-10% lower root dry weight at 50 and 75 DAT compared to BRRI dhan-31. The photosynthetic rate was higher (20 μ mol m-2/sec-1) in BRRI dhan-3l at 35 DAT (maximum tillering stage) but at 65 DAT, Sonarbangla-l had higher photosynthetic rate of 19.5 μ mol m-2 sec-1. BRRI dhan-3l had higher panicles/plant than Sonarbangla-1, but Sonarbangla-1 had higher number of grains/panicle, 1000-grain weight and grain yield than BRRI dhan-31. In 2002, BRRI dhan-31 had the highest plant height at 25 DAT, but at 75 DAT, BRRI hybrid dhan-l had the highest plant height. Sonarbangla-1 had the largest leaf area at 25 and 50 DAT followed by BRRI dhan-31, but at 75 DAT, BRRI dhan-31 had the largest leaf area. The highest shoot dry matter was observed in BRRI dhan-31 followed by Sonarbangla-1 at all DATs. Sonarbangla-1 had the highest rooting depth and root dry weight at all DATs. BRRI dhan-31 gave the highest number of panicles/plant followed by Sonarbangla-I, BRRI hybrid dhan-l had the highest grains/panicle followed by BRRI dhan-31 and Sonarbangla-I had the highest 1000-grain weight followed by BRRI dhan-31. The highest amount of grains/plant (34.6 g) was obtained from BRRI dhan-31. Key Words: Shoot dry matter; root dry weight; leaf area; photosynthesis; grain yield. DOI: 10.3329/bjar.v34i1.5755Bangladesh J. Agril. Res. 34(1) : 67-73, March 2009


1997 ◽  
Vol 75 (2) ◽  
pp. 213-219 ◽  
Author(s):  
Xiuming Hao ◽  
Beverley A. Hale ◽  
Douglas P. Ormrod

Tomato (Lycopersicon esculentum Mill.) plants were exposed, in controlled environments with 2.7 kJ/(m2 ∙ day) background ultraviolet-B (UV-B) radiation from fluorescent and incandescent lamps, to ambient (380 μL ∙ L−1) or elevated (600 μL−1) CO2 combined with a total of 7.2 or 13.1 kJ/(m2 ∙ day) UV-B radiation to determine effects on growth and photosynthesis. Ten consecutive days of exposure to the higher level of UV-B significantly reduced total and stem dry weight, leaf area, and plant height compared with the lower level. Only leaf area and plant height were significantly reduced after 19 consecutive days of exposure. To investigate whether plants recover from UV-B damage, the UV-B exposures were halted for 3 days after 19 days of UV-B exposure and then restarted for a further 2 days. The largest reduction in plant growth was found after 3 days with no UV-B followed by 2 days of the higher level of UV-B. Plants did not recover from UV-B damage during the 3 days with background UV-B. Significant CO2xUV-B interactions were detected on stem dry weight after 10 consecutive days of the higher level of UV-B and on total dry weight, leaf dry weight, stem dry weight, and plant height after 3 days with no UV-B followed by 2 days of the higher level of UV-B. The higher dose of enhanced UV-B resulted in more severe damage at 600 μL ∙ L−1 CO2, than at ambient CO2. The higher level of UV-B did not affect the leaf net photosynthesis rate on a leaf area basis, although this UV-B level may have inhibited tomato growth through reducing the photosynthetic area. UV-absorbing compounds in leaves in the highest UV-B radiation level for 19 days were greater than for leaves with the lower dose. These UV-absorbing compounds in the higher UV-B dose diminished more than in the lower dose plants during the 3 days without UV-B. The UV-absorbing compounds maintained by plants exposed to the highest level of UV-B radiation may have protected plants from UV-B damage, particularly between 10 and 19 consecutive days of exposure. Key words: CO2, growth, Lycopersicon esculentum Mill., photosynthesis, tomato, ultraviolet-B radiation (UV-B), UV-absorbing compounds.


Author(s):  
Ogbuehi HC ◽  
Ibe PK

A pot experiment was conducted under rainfed condition to study the effect of water hyacinth compost on the morpho-physiological parameters of soybean (Glycine max L.) at the Teaching and Research Farm of Faculty of Agriculture and Veterinary Medicine, Imo State University, Owerri. The treatments were control (T1) 100g (T2), 150g (T3) and 200g (T4) of water hyacinth compost and replicated four times. The treatments were arranged in Complete Randomized Design (CRD). The parameters measured were plant height, number of leaves, leaf area (cm2), leaf area index, relative growth rate (RGR), Net assimilation rate (NAR), shoot dry weight(g), yield and yield components (Number of pods, pods weight, 100 seed weight). The results obtained indicated that T3 significantly produced highest plant height (57.6cm) compare to control. While it was observed that T4 (200g) significantly produced the highest number of leaves (233.25), leaf area (631.80cm2), shoot dry weight (15.445g), number of pods (129.75), pod weights (25.38g) seed weight (7.23g) and yield (0.72kg/ha) relative to control and other treatment levels. Root parameters were also significantly improved by the rates of water hyacinth application compared to control. It will be worthy to note that there was no nodulation perhaps that was why the yield was poor. The results showed that soybean growth can effectively be improved with incorporation of water hyacinth into soil.


2001 ◽  
Vol 19 (2) ◽  
pp. 65-68
Author(s):  
Sandra B. Wilson ◽  
Nihal C. Rajapakse

Abstract Plant response to photoselective plastic films with varying spectral distribution properties was tested using three sub-tropical perennials: golden shrimp plant (Pachystachys lutea), Persian shield (Strobilanthes dyerianus), and cat whiskers (Orthosiphon stamineus). Films were designated YXE-10 [far-red (FR) light-absorbing film] and SXE-4 [red (R) light absorbing film]. Light transmitted through YXE-10 films reduced plant height (stem length) of golden shrimp plant and cat whiskers by 10 and 20%, respectively. Light transmitted through SXE-4 films increased plant height by 9% for golden shrimp plant but did not significantly increase stem length of Persian shield and cat whiskers species. Chlorophyll, leaf area, and mean days to flower generally were not affected by photoselective films, with the exception that cat whisker plants grown under YXE-10 films had reduced leaf area when compared to plants grown under SXE-4 or control films. As compared to the control film, light transmitted through YXE-10 films reduced leaf dry weight by 22–31% and stem dry weight by 19–28%, depending on the plant species. Root dry weight was not affected by spectral films.


HortScience ◽  
2019 ◽  
Vol 54 (11) ◽  
pp. 2056-2062 ◽  
Author(s):  
Asmita Paudel ◽  
Ji Jhong Chen ◽  
Youping Sun ◽  
Yuxiang Wang ◽  
Richard Anderson

Sego SupremeTM is a designated plant breeding and introduction program at the Utah State University Botanical Center and the Center for Water Efficient Landscaping. This plant selection program introduces native and adapted plants to the arid West for aesthetic landscaping and water conservation. The plants are evaluated for characteristics such as color, flowering, ease of propagation, market demand, disease/pest resistance, and drought tolerance. However, salt tolerance has not been considered during the evaluation processes. Four Sego SupremeTM plants [Aquilegia barnebyi (oil shale columbine), Clematis fruticosa (Mongolian gold clematis), Epilobium septentrionale (northern willowherb), and Tetraneuris acaulis var. arizonica (Arizona four-nerve daisy)] were evaluated for salt tolerance in a greenhouse. Uniform plants were irrigated weekly with a nutrient solution at an electrical conductivity (EC) of 1.25 dS·m−1 as control or a saline solution at an EC of 2.5, 5.0, 7.5, or 10.0 dS·m−1 for 8 weeks. After 8 weeks of irrigation, A. barnebyi irrigated with saline solution at an EC of 5.0 dS·m−1 had slight foliar salt damage with an average visual score of 3.7 (0 = dead; 5 = excellent), and more than 50% of the plants were dead when irrigated with saline solutions at an EC of 7.5 and 10.0 dS·m−1. However, C. fruticosa, E. septentrionale, and T. acaulis had no or minimal foliar salt damage with visual scores of 4.2, 4.1, and 4.3, respectively, when irrigated with saline solution at an EC of 10.0 dS·m−1. As the salinity levels of treatment solutions increased, plant height, leaf area, and shoot dry weight of C. fruticosa and T. acaulis decreased linearly; plant height of A. barnebyi and E. septentrionale also declined linearly, but their leaf area and shoot dry weight decreased quadratically. Compared with the control, the shoot dry weights of A. barnebyi, C. fruticosa, E. septentrionale, and T. acaulis decreased by 71.3%, 56.3%, 69.7%, and 48.1%, respectively, when irrigated with saline solution at an EC of 10.0 dS·m−1. Aquilegia barnebyi and C. fruticosa did not bloom during the experiment at all treatments. Elevated salinity reduced the number of flowers in E. septentrionale and T. acaulis. Elevated salinity also reduced the number of shoots in all four species. Among the four species, sodium (Na+) and chloride (Cl–) concentration increased the most in A. barnebyi by 53 and 48 times, respectively, when irrigated with saline solution at an EC of 10.0 dS·m−1. In this study, C. fruticosa and T. acaulis had minimal foliar salt damage and less reduction in shoot dry weight, indicating that they are more tolerant to salinity. Epilobium septentrionale was moderately tolerant to saline solution irrigation with less foliar damage, although it had more reduction in shoot dry weight. On the other hand, A. barnebyi was the least tolerant with severe foliar damage, more reduction in shoot dry weight, and a greater concentration of Na+ and Cl–.


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