Ferrets are sexually dimorphic, male ferrets weigh between 1000g and 2000g, and females between 600g and 900g (Landcare Research, 2008). They have a long and slender body which is 48cm to 56cm long (including the tail). They have large canine teeth (34 teeth in total). Each paw has a set of five non-retractable claws (Duda, 2003). Ferrets have three basic colour variations: dark (similar to the polecat), white underfur with brownish guard hairs (referred to as sandy or pastel), and all white (albino). All three of these variations are found in New Zealand (Jeffares, 1986). In Europe, wild-type colour variations are more common in populations that have been feral for several generations.
FACTSHEETS FOR FARMERS www.plantwise.org Created in Tanzania , September 2012 Come together to mass trap Mango fruit fly Recognize the problem Mango fruit flies ("Vidudu" in Swahili) inject their eggs into young fruits. The eggs hatch into larvae that grow and eat inside the fruit. You cannot control them with chemicals because larvae are hidden inside fruit. The larvae cause the fruit to rot and the fruit drops down before ripening. Some attacked fruits remain attached to the tree, but are of low quality. The fruit fly adult is a small winged...
FACTSHEETS FOR FARMERS www.plantwise.org Created in Grenada , October 2012 Control of Moko disease Recognize the problem Moko is a disease that affects bananas and other crops within the banana family causing a reduction in yield and sometimes total death of the plant. Plants wilt, leaves turn yellow and drop off, brown streaks and patches occur on the stem. Symptoms include the navel (male bud) becoming black and dropping, uneven and pre-mature ripening of fruits, blackening of the inside of the fruit and death of plants. Background The...
FACTSHEETS FOR FARMERS www.plantwise.org Created in Kenya , December 2012 Woodiness on Passion Fruit Recognize the problem This is one of the most dangerous sicknesses of the purple passion fruit. It makes the passion fruit woody and hard, hence the name "woodiness". The disease is visible on leaves as a light or dark green mosaic pattern often with light yellow discolouration. Infected fruits appear small and shapeless with hardy peel and small juice area. Sometimes the disease makes the affected fruit crack. Background Woodiness disease is...
FACTSHEETS FOR FARMERS www.plantwise.org Created in India , November 2012 Sugarcane Woolly Aphids Recognize the problem The sugarcane woolly aphid is a pest that has profuse white coloured woolly coating around it. It is often mistaken for a mealybug. The white powder on the ground and leaves confirms the presence of the aphids. If uncontrolled, it spreads very quickly and can cause yield losses of up to 20%. This pest is locally known as “ Panju asuvini ” (Tamil). The nymphs and adults of the aphid remain on the under surface of the...
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Musa x paradisiaca
Musa × paradisiaca
Musa × paradisiaca
Musa × paradisiaca
Musa × paradisiaca
Musa × paradisiaca
Musa × paradisiaca
Musa × paradisiaca Musa paradisiaca
C. imbricatus is a coarse, rhizomatous perennial, 70-150 cm tall;rhizomes short, 1-3 cm long, 5-10 mm thick, hardened;roots coarse. Culms erect, trigonous, often subtriquetrous distally, firm, coarsely ribbed, smooth, 3.5 -10 mm wide, sheathing bases 1-3 cm wide. Leaves 3-7;sheaths eligulate, spongy-thickened and purple-black proximately, fading to brown streaked with black distally;ligule absent;blades linear, folded to V shaped proximally, plicate distally, 35-90 cm ? 4-15 (-18) mm, with numerous cross veinlets, scabrous on the margins, abaxial mid-vein, and adaxial lateral veins, long-attenuate to triquetrous apex. Inflorescence a compound umbel-like corymb with ascending rays, 12-30 ?14-30 (-40) cm;involucral bracts 5-10, leaf-like, spreading, ascending to horizontal, the lowermost to 90 cm long;rays 6-12, to 25 cm long;spikes linear-cylindric, 1-6 (-8) cm ? 3-10 (-15) mm, in subradiate groups of (1-) 3-20 at ray tips, with (20-) 30-130 (-160) densely disposed spikelet, compressed, often slightly twisted, 3-6 ? 1-1.4 mm, acute to obtuse at apex, obtuse at base, with 8-22 florets. Stamens 3, the anthers 0.2 - 0.5 mm long, apiculate;styles 3-branched. Achene trigonous, dorsi-ventrally compressed, with the adaxial face plane and the abaxial faces broadly rounded, ellipsoid to ellipsoid-obovoid, 0.5-0.6 ?0.3-0.4 mm, very finely puncticulate to essentially smooth and glossy at maturity, dull whitish to stramineous (Acevedo-Rodr’guez and Strong, 2005).
C. imbricatus is a common weed in rice plantations and banana fields in tropical and temperate Asia (Mangoensoekardjo and Pancho, 1975;Soerjani et al., 1987;Noda et al., 1994;Li, 1998;Koo et al., 2000).
P. hysterophorus is an erect, much-branched with vigorous growth habit, aromatic, annual (or a short-lived perennial), herbaceous plant with a deep taproot. The species reproduces by seed. In its neotropical range it grows to 30-90 cm in height (Lorenzi, 1982, Kissmann and Groth, 1992), but up to 1.5 m, or even 2.5 m, in exotic situations (Haseler, 1976, Navie et al., 1996). Shortly after germination the young plant forms a basal rosette of pale green, pubescent, strongly dissected, deeply lobed leaves, 8-20 cm in length and 4-8 cm in width. The rosette stage may persist for considerable periods during unfavourable conditions (such as water or cold stress). As the stem elongates, smaller, narrower and less dissected leaves are produced alternately on the pubescent, rigid, angular, longitudinally-grooved stem, which becomes woody with age. Both leaves and stems are covered with short, soft trichomes, of which four types have been recognized and are considered to be of taxonomic importance within the genus (Kohli and Rani, 1994).;Flower heads are both terminal and axillary, pedunculate and slightly hairy, being composed of many florets formed into small white capitula, 3-5 mm in diameter. Each head consists of five fertile ray florets (sometimes six, seven or eight) and about 40 male disc florets. The first capitulum forms in the terminal leaf axil, with subsequent capitula occurring progressively down the stem on lateral branches arising from the axils of the lower leaves. Thousands of inflorescences, forming in branched clusters, may be produced at the apex of the plant during the season. Seeds (achenes) are black, flattened, about 2 mm long, each with two thin, straw-coloured, spathulate appendages (sterile florets) at the apex which act as air sacs and aid dispersal.
P. hysterophorus is known to reduce the yield of various crops and to compete with pasture species in various countries. However, the yield loss and specific effects on the crops have not been quantified in all countries (Rubaba et al., 2017).;In Australia, the main impact of P. hysterophorus has been in the pastoral region of Queensland, where it replaces forage plants, thereby reducing the carrying capacity for grazing animals (Haseler, 1976, Chippendale and Panetta, 1994). Serious encroachment and replacement of pasture grasses has also been reported in India (Jayachandra, 1971) and in Ethiopia (Tamado, 2001, Taye, 2002). The weed is also able to invade natural ecosystems, and has caused total habitat changes in native Australian grasslands and open woodlands (McFadyen, 1992).;In India, the yield losses are reported as up to 40% in several crops and a 90% reduction of forage production (Gnanavel, 2013). P. hysterophorus is now being reported from India as a serious problem in cotton, groundnuts, potatoes and sorghum, as well as in more traditional crops such as okra (Abelmoschus esculentus), brinjal (Solanum melongena), chickpea and sesame (Kohli and Rani, 1994), and is also proving to be problematic in a range of orchard crops, including vineyards, olives, cashew, coconut, guava, mango and papaya (Tripathi et al., 1991, Mahadevappa, 1997, Gnanavel, 2013).;Similar infestations of sugarcane and sunflower plantations have recently been noted in Australia (Parsons and Cuthbertson, 1992, Navie et al., 1996), whilst in Brazil and Kenya, the principal crop affected is coffee (Njoroge, 1989, Kissmann and Groth, 1992). In Ethiopia, parthenium weed was observed to grow in maize, sorghum, cotton, finger millet (Eleusine coracana), haricot bean (Phaseolus vulgaris), tef (Eragrostis tef), vegetables (potato, tomato, onion, carrot) and fruit orchards (citrus, mango, papaya and banana) (Taye, 2002). In Pakistan, the weed has been reported from number of crops, including wheat, rice, sugarcane, sorghum, maize, squash, gourd and water melon (Shabbir 2006, Shabbir et al. 2011, Anwar et al. 2012).;In Mexico, the species is reported as a weed in cotton, rice, sugarcane, Citrus spp, beans, safflower, sunflower, lentils, corn, mango, okra, bananas, tomato, grapes, alfalfa, chili peppers, luffa, marigolds and other vegetables and fruit orchards. It is also a weed in nurseries. In Argentina is reported as a weed of tobacco fields (CONABIO, 2018).;Gnanavel (2013) also reports the following detrimental effects of P. hysterophorus on crops: it inhibits nitrogen fixing bacteria in legumes, the vast quantity of pollen it produces (ca. 624 million/plants) inhibits fruit setting, it is an alternative host for viruses that cause diseases in crop plants, and it is an alternative host for mealy bugs.
Fusarium wilt of bananas is caused by F. oxysporum f.sp. cubense, a common soil inhabitant. Other formae speciales attack a wide variety of other crops, including cotton, flax, tomatoes, cabbages, peas, sweet potatoes, watermelons and oil palms.;The formae speciales of Fusarium oxysporum each produce three types of asexual spores. The macroconidia (22-36 x 4-5 µm, see Wardlaw, 1961 for measurements) are produced most frequently on branched conidiophores in sporodochia on the surface of infected plant parts or in artificial culture. Macroconidia may also be produced singly in the aerial mycelium, especially in culture. The macroconidia are thin-walled with a definite foot cell and a pointed apical cell. Oval or kidney-shaped microconidia (5-7 x 2.5-3 µm) occur on short microconidiophores in the aerial mycelium and are produced in false heads. Both macroconidia and microconidia may also be formed in the xylem vessel elements of infected host plants, but the microconidia are usually more common. The fungus may be spread by macroconidia, microconidia and mycelium within the plant as well as outside the plant. Illustrations of the conidia have been published (Nelson et al., 1983).;Chlamydospores (9 x 7 µm) are thick-walled asexual spores that are usually produced singly in macroconidia or are intercalary or terminal in the hyphae. The contents are highly refractive. Chlamydospores form in dead host-plant tissue in the final stages of wilt development and also in culture. These spores can survive for an extended time in plant debris in soil.;Mutation in culture is a major problem for those working with vascular wilt isolates of F. oxysporum. The sporodochial type often mutates to a 'mycelial' type or to a 'pionnotal' type. The former has abundant aerial mycelium, but few macroconidia, whereas the latter produces little or no aerial mycelium, but abundant macroconidia. These cultures may lose virulence and the ability to produce toxins. Mutants occur more frequently if the fungus is grown on a medium that is rich in carbohydrates.
Banana;The various symptoms of Fusarium wilt on banana are described and well illustrated by Ploetz and Pegg (1999).;The first external symptoms of Fusarium wilt on bananas is a faint off-green to pale-yellow streak or patch at the base of the petiole of one of the two oldest leaves. The disease can then progress in different ways. The older leaves can yellow, beginning with patches at the leaf margin. Yellowing progresses from the older to the younger leaves until only the recently unfurled or partially unfurled centre leaf remains erect and green. This process may take from 1 to 3 weeks in cultivar 'Gros Michel'. Often the yellow leaves remain erect for 1-2 weeks or some may collapse at the petiole and hang down the pseudostem. In contrast to this 'yellow syndrome', leaves may remain completely green except for a petiole streak or patch but collapse as a result of buckling of the petiole. The leaves fall, the oldest first, until they hang about the plant like a skirt. Eventually, all leaves on infected plants fall down and dry up. The youngest are the last to fall and often stand unusually erect.;Splitting of the base of the pseudostem is another symptom as is necrosis of the emerging heart leaf. Other symptoms include irregular, pale margins on new leaves and the wrinkling and distortion of the lamina. Internodes may also shorten (Stover, 1962, 1972, Jones, 1994, Moore et al., 1995).;The characteristic internal symptom of Fusarium wilt is vascular discoloration. This varies from one or two strands in the oldest and outermost pseudostem leaf sheaths in the early stages of disease to heavy discoloration throughout the pseudostem and fruit stalk in the later disease stages. Discoloration varies from pale yellow in the early stages to dark red or almost black in later stages. The discoloration is most pronounced in the rhizome in the area of dense vascularization where the stele joins the cortex. When symptoms first appear, a small or large portion of the rhizome may be infected. Eventually, almost the entire differentiated vascular system is invaded. The infection may or may not pass into young budding suckers or mature 'daughter' suckers. Where it does, discoloration of vascular strands may be visible in the excised sucker. Usually, suckers less than 1.5 m tall and ca. 4 months old do not show external symptoms. Where wilt is epidemic and spreading rapidly, suckers are usually infected and seldom grow to produce fruit. Above- and below-ground parts of affected plants eventually rot and die.;Fusarium wilt was reported to occur on banana cultivars of the 'Mutika-Lujugira' (AAA genome) subgroup in East Africa above 1400 m. Internal symptoms were much less extensive than those described above and external symptoms more subtle, comprising thin pseudostems and small fingers. Nevertheless, symptomatic plants were recognized by smallholders and were rogued. These mild symptoms were initially believed to be indicative of an attack on a plant whose defences have been weakened as a result of cooler conditions or other predisposing factors at altitude (Ploetz et al., 1994). Given the importance of this banana group, also referred to locally as ÔEast African highland bananasÕ, to local trade and as a staple food, further investigation was merited. This revealed that the disorder also affected non-indigenous banana types, including Cavendish and Bluggoe (which were not affected by Fusarium wilt) and was related to abnormal soil nutrient levels and farm management practice. Discoloration similar to that caused by F. oxysporum f.sp. cubense was observed in vascular tissues of affected plants. Fusarium pallidoroseum (syn. Fusarium semitectum) was consistently isolated from such tissues but found to be non-pathogenic. F. oxysporum was not recovered (Kangire and Rutherford, 2001, Rutherford, 2006).
F. oxysporum f.sp. cubense is one of around 100 formae speciales (special forms) of F. oxysporum which cause vascular wilts of flowering plants (Gerlach and Nirenberg, 1982). Hosts of the various formae speciales are usually restricted to a limited and related set of taxa. As currently defined, F. oxysporum f.sp. cubense affects the following species in the order Zingiberales: in the family Musaceae, Musa acuminata, M. balbisiana, M. schizocarpa and M. textilis, and in the family Heliconeaceae, Heliconia caribaea, H. chartacea, H. crassa, H. collinsiana, H. latispatha, H. mariae, H. rostrata and H. vellerigera (Stover, 1962, Waite, 1963). Additional hosts include hybrids between M. acuminata and M. balbisiana, and M. acuminata and M. schizocarpa.;F. oxysporum f.sp. cubense may survive as a parasite of non-host weed species. Three species of grass (Paspalum fasciculatum, Panicum purpurascens [ Brachiaria mutica ] and Ixophorus unisetus) and Commelina diffusa have been implicated (Waite and Dunlap, 1953).
Adult Papuana huebneri are black, shiny and 15-20 mm long. The size and number of head horns in taro beetles varies between species and sexes;P. huebneri has only one small horn, which is larger in the male than the female (Macfarlane, 1987a).
Taro beetles can be detected by: (1) digging up wilting taro plants and examining them for signs of damage;(2) using light traps, particularly on moonless and rainy nights;and (3) sampling wild plant species (e.g. banana, sugarcane and grasses such as Paspalum spp. and Brachiaria mutica) at breeding sites, especially along river banks, on rotting logs and in compost heaps (Carmichael et al., 2008;Tsatsia and Jackson, 2014;TaroPest, 2015).
Adult taro beetles burrow into the soft trunks, plant bases and corms of a range of plants, including taro, making large holes or cavities up to 2 cm in diameter (McGlashan, 2006). The feeding tunnels and associated frass may be visible in infested corms (Biosecurity Australia, 2011). The amount of damage to the crop depends on the age of the plants when attacked and the density of infestation. Feeding activity can cause wilting and even the death of affected plants, particularly in young plants if the beetles bore into the growing points. Older plants infested by beetles grow slowly and a few or all of the leaves wilt (TaroPest, 2015). In severely damaged plants tunnels may run together to form large cavities, making the damaged corms more susceptible to fungal infections (Macfarlane, 1987a;Onwueme, 1999). Similar symptoms of damage are caused to other root crops, e.g. sweet potato, yams and potato (McGlashan, 2006). Taro beetles can ring-bark young tea, cocoa and coffee plants in the field and bore into seedlings of oil palm and cocoa (Aloalii et al., 1993).
Papuana huebneri is one of at least 19 species of known taro beetles native to the Indo-Pacific region;it is native to Papua New Guinea, the Molucca Islands in Indonesia, the Solomon Islands and Vanuatu, and has been introduced to Kiribati. Taro (Colocasia esculenta) is an important crop in these countries;high infestations of P. huebneri can completely destroy taro corms, and low infestations can reduce their marketability. The beetle also attacks swamp taro or babai (Cyrtosperma chamissonis [ Cyrtosperma merkusii ]), which is grown for consumption on ceremonial occasions. Infestations of taro beetles, including P. huebneri, have led to the abandonment of taro and swamp taro pits in the Solomon Islands and Kiribati, resulting in the loss of genetic diversity of these crops and undermining cultural traditions. P. huebneri also attacks a variety of other plants, although usually less seriously. Management today relies on an integrated pest management strategy, combining cultural control measures with the use of insecticides and the fungal pathogen Metarhizium anisopliae.
Papuana huebneri is a pest of taro (Colocasia esculenta;known as ‘dalo’ in Fijian;McGlashan, 2006) (Masamdu, 2001;International Business Publications, 2010), which is grown primarily as a subsistence crop in many Pacific Island countries, including Kiribati, Papua New Guinea, the Solomon Islands and Vanuatu, where P. huebneri is found (Aloalii et al., 1993). Taro also has value in gift-giving and ceremonial activities (Braidotti, 2006;Lal, 2008). The beetle also attacks swamp taro or babai (Cyrtosperma merkusii or Cyrtosperma chamissonis), which is grown for consumption on ceremonial occasions (Food and Agriculture Organization, 1974;Dharmaraju, 1982;International Business Publications, 2010).
Other plants attacked by Papuana huebneri include tannia (Xanthosoma sagittifolium), bananas (Musa spp.), Canna lily (Canna indica), pandanus (Pandanus odoratissimus [ Pandanus utilis or P. odorifer ]), the bark of tea (Camellia sinensis), coffee (Coffea spp.) and cocoa (Theobroma cacao), the fern Angiopteris evecta (Masamdu, 2001), and occasionally the Chinese cabbage Brassica chinensis [ Brassica rapa ] (International Business Publications, 2010).
Species of Papuana behave similarly to each other and feed on the same host plants (TaroPest, 2015). For taro beetles in general, primary host plants other than taro include giant taro (Alocasia macrorrhizzos), Amorphophallus spp., the fern Angiopteris evecta, banana (Musa spp.) and tannia (Xanthosoma sagittifolium). Secondary hosts include pineapple (Ananas comosus), groundnut (Arachis hypogaea), betel nut (Areca catechu), cabbage (Brassica oleracea), canna lily (Canna indica), coconut (Cocos nucifera), Commelina spp., Crinum spp., yam (Dioscorea spp.), oil palm (Elaeis guineensis), sweet potato (Ipomoea batatas), Marattia spp., pandanus (Pandanus odoratissimus [ Pandanus utilis or P. odorifer ]), Saccharum spp. including sugarcane (Saccharum officinarum) and Saccharum edule [ Saccharum spontaneum var. edulis ], and potato (Solanum tuberosum);they occasionally ring bark young tea (Camellia sinensis), coffee (Coffea spp.) and cocoa (Theobroma cacao) plants (Macfarlane, 1987b;Aloalii et al., 1993;Masamdu and Simbiken, 2001;Masamdu, 2001;Tsatsia and Jackson, 2014;TaroPest, 2015).
Herbaceous, twining or creeping vine, attaining 3 m or more in length. Stems cylindrical, usually reddish, with long, erect, yellowish, non-glandular hairs. Leaves alternate, 5-palmately compound;leaflets 4-14 x 2-6 cm, oblanceolate or elliptical, the apex and base acuminate, the margins entire and ciliate, hispidulous to glabrate on both surfaces. Flowers in dichasial cymes;peduncles shorter than the petioles, hairy;bracts deciduous;sepals subequal or unequal, 1.5-2 cm long, with long, yellowish hairs;corolla funnel-shaped, white, 2.5-3 cm x 4-4.5 cm;five stamens, white;stigma bilobed, white. Fruit capsular, 4-valvate, subglobose, 1-1.5 cm in diameter, light brown, glabrous, surrounded by the persistent sepals. Four seeds per fruit, obtusely triangular, 5-6 mm long, brown, glabrous (Acevedo-Rodríguez, 2005;Austin et al., 2012).
M. aegyptia can be easily recognized in the field by the 5-digitate leaves with entire leaflets, and the long, erect hairs covering the stems and calyx.
Merremia aegyptia is an annual climbing herb that acts as a pioneer species in disturbed sites in tropical regions. It is considered a weed in most countries where it occurs and it has been included in the Global Compendium of Weeds as an agricultural and environmental weed (Randall, 2012). The species is native to tropical America and Africa and listed as invasive in Cuba, India, Australia and Hawaii.
M. aegyptia is a relatively common weed in sugarcane (Brazil, Lesser Antilles, Reunion) and maize fields (Guatemala, Brazil, Nigeria), where it climbs up plants, bending and entangling their stems (Standley and Williams, 1970;Fournet and Hammerton, 1991;Lima e Silva et al., 2004;Valery, 2006;Chikoye et al., 2009;Correia et al., 2010;Correia, 2016). It has also been reported in cotton (Cardoso et al., 2010), banana (Isaac et al., 2009), rice (Ismaila et al., 2015), green pepper (Coelho et al., 2013), muskmelon (Teófilo et al., 2012), yam (Fournet and Hammerton, 1991) and coffee plantations (Gavilanes et al., 1988).
T. alata is an herbaceous vine, creeping or climbing, twining, 2-3 m in length. Stems cylindrical, slender, puberulous. Leaves opposite;blades 4.5-10.5 × 3.2-6 cm, ovate, lobed, chartaceous, the apex acute, the base subcordiform;upper surface dark green, dull, pubescent;lower surface pale green, dull, with prominent venation;petioles 4-8 cm long, winged, pubescent. Flowers axillary, solitary;pedicels pubescent, 4-5 cm long;bracts green, ovate, pubescent, 1.5 cm long, covering the calyx and the corolla tube. Calyx yellowish green, with 12 filiform lobes, approximately 4 mm long;corolla orange, pale yellow, or less frequently whitish, infundibuliform, with 5 lobes, the tube approximately 2.5 cm long, narrow at the base, dark violet inside, the lobes approximately 2.5 cm long with the apex truncate, the limb approximately 5 cm in diameter;stamens with glandular hairs on the basal portion. Capsules approximately 4 mm long, depressed-globose to 4-lobed at the base, the upper half in the form of a beak, dehiscent by two valves;seeds 2 or 4, 1.2-1.5 mm long, semicircular, reticulate (Acevedo-Rodríguez, 2005). Several cultivars have been developed, including some with white, yellow, and even pinkish-coloured flowers (Queensland Department of Primary Industries and Fisheries, 2011).
T. alata is an herbaceous vine, often cultivated as an ornamental, which has escaped and naturalized mostly in disturbed areas in tropical, subtropical and warmer temperate regions of the world (Starr et al., 2003;Meyer and Lavergne, 2004;Queensland Department of Primary Industries and Fisheries, 2011). It is a fast-growing vine with the capability of reproducing sexually by seeds and vegetatively by cuttings, fragments of stems and roots (Starr et al., 2003;Vibrans, 2009). Once established, it completely smothers native vegetation by killing host-trees, out-competing understory plants, and negatively affecting the germination and establishment of seedlings of native species (Starr et al., 2003;Meyer and Lavergne, 2004). T. alata is included in the Global Compendium of Weeds (Randall, 2012) and it is also considered an aggressive invasive plant in Australia, Japan, Singapore, Costa Rica, Cuba, Puerto Rico, Brazil, Colombia, Paraguay, and numerous islands in the Pacific including Hawaii and French Polynesia.
T. alata is considered a weed affecting mostly plantation crops such as Citrus, coffee, mango, and banana plantations (Vibrans, 2009).