{"id":1541,"date":"2024-02-18T15:25:46","date_gmt":"2024-02-18T09:55:46","guid":{"rendered":"https:\/\/lotusarise.com\/qna\/?p=1541"},"modified":"2024-04-03T07:01:11","modified_gmt":"2024-04-03T01:31:11","slug":"q-consider-the-following-organisms","status":"publish","type":"post","link":"https:\/\/lotusarise.com\/qna\/upsc\/q-consider-the-following-organisms","title":{"rendered":"Q.\u00a0Consider the following organisms:"},"content":{"rendered":"\n<ol class=\"wp-block-list\">\n<li>Agaricus<\/li>\n\n\n\n<li>Nostoc<\/li>\n\n\n\n<li>Spirogyra<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">Which of the above is\/are used as&nbsp;<strong>biofertilizer\/biofertilizers<\/strong>?<\/p>\n\n\n\n<ul class=\"mcq wp-block-list\">\n<li>1 and 2<\/li>\n\n\n\n<li>2 only<\/li>\n\n\n\n<li>2 and 3<\/li>\n\n\n\n<li>3 only<\/li>\n<\/ul>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>Answer: (b) 2 only<\/strong><\/p>\n<\/blockquote>\n\n\n\n<h5 class=\"wp-block-heading\" id=\"biofertilizers\">Biofertilizers<\/h5>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Biofertilizers are&nbsp;<strong>substance that contains microbes, which helps in promoting the growth of plants and trees by increasing the supply of essential nutrients to the plants<\/strong>.<\/li>\n\n\n\n<li>It comprises living organisms which include&nbsp;<strong>mycorrhizal fungi, blue-green algae, and bacteria.<\/strong>\n<ul class=\"wp-block-list\">\n<li>Mycorrhizal fungi preferentially withdraw minerals from organic matter for the plant whereas cyanobacteria are characterized by the property of nitrogen fixation.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Benefits of biofertilizers<\/strong>\n<ul class=\"wp-block-list\">\n<li>Biofertilizers fix atmospheric nitrogen in the soil and root nodules of legume crops and make it available to the plant.<\/li>\n\n\n\n<li>They solubilise the insoluble forms of phosphates like tricalcium, iron and aluminium phosphates into available forms.<\/li>\n\n\n\n<li>They scavenge phosphate from soil layers.<\/li>\n\n\n\n<li>They produce hormones and anti metabolites which promote root growth.<\/li>\n\n\n\n<li>They decompose organic matter and help in mineralization in soil.<\/li>\n\n\n\n<li>When applied to seed or soil, biofertilizers increase the availability of nutrients and improve the yield by 10 to 25% without adversely affecting the soil and environment.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Types of biofertilizers<\/strong>\n<ul class=\"wp-block-list\">\n<li>Based on type of microorganism, the bio-fertilizer can also be classified as follows:\n<ul class=\"wp-block-list\">\n<li><strong>Bacterial Biofertilizers<\/strong>: e.g. Rhizobium, Azospirilium, Azotobacter, Phosphobacteria.<\/li>\n\n\n\n<li><strong>Fungal Biofertilizers<\/strong>: e.g. Mycorhiza<\/li>\n\n\n\n<li><strong>Algal Biofertilizers<\/strong>: e.g. Blue Green Algae (BGA) and Azolla.<\/li>\n\n\n\n<li><strong>Actinimycetes Biofertilizer<\/strong>: e.g. Frankia.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>Bio-fertilizer are mostly cultured and multiplied it the laboratory. However, blue green algae and azolla can be mass-multiplied in the field.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Characteristics Features of common Biofertilizers<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong>Rhizobium<\/strong>: Rhizobium is relatively more effective and widely used biofertilizer. Rhizobium, in association wit legumes, fixes atmospheric N. The legumes and their symbiotic association with the rhizobium bacterium result in the formation of root nodules that fix atmospheric N. Successful nodulation of leguminous crop by rhizobium largely depends on the availability of a compatible stain for a particular legume. Rhizobium population in the soil is dependent on the presence of legumes crops in field. In the absence of legumes the population of rhizobium in the soil diminishes.<\/li>\n\n\n\n<li><strong>Azospirillum<\/strong>: Azospirillum is known to have a close associative symbiosis with the higher plant system. These bacteria have association with cereals like; sorghum, maize, pearl millet, finger millet, foxtail millet and other minor millets and also fodder grasses.<\/li>\n\n\n\n<li><strong>Azotobacter<\/strong>:&nbsp; It is a common soil bacterium.&nbsp;<em>Azotobacter&nbsp;chroococcum&nbsp;<\/em>is present widely in Indian soil. Soil organic matter is the important factor that decides the growth of this bacteria.<\/li>\n\n\n\n<li><strong>Blue Green Algae (BGA<\/strong>): Blue green algae are referred to as rice organisms because of their abundance in the rice field. Many species belonging to the genera,&nbsp;<strong>Tolypothrix, Nostic, Schizothrix, Calothrix, Anoboenosois and Plectonema&nbsp;<\/strong>are abundant in tropical conditions. Most of the nitrogen fixation BGA are filamenters, consisting of chain of vegetative cell including specialized cells called heterocyst which function as a micronodule for synthesis and N fixing machinery.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h6 class=\"wp-block-heading\" id=\"nostoc\">Nostoc<\/h6>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Nostoc is a genus of&nbsp;<strong>blue-green algae&nbsp;or cyanobacteria<\/strong>. They are prokaryotic and perform photosynthesis.<\/li>\n\n\n\n<li>They are found mainly in freshwater as free-living colonies or attached to rocks or at the bottom of lakes. They are also found on tree trunks. They are also found as an algal component of lichens in certain bryophytes (Anthoceros).<\/li>\n\n\n\n<li>They are capable of nitrogen-fixing and perform photosynthesis. They are also present as an endosymbiont to fungus.<\/li>\n<\/ul>\n\n\n\n<h6 class=\"wp-block-heading\" id=\"agaricus\">Agaricus<\/h6>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Agaricus is a&nbsp;<strong>genus of mushroom-forming fungi&nbsp;<\/strong>containing both&nbsp;<strong>edible and poisonous species<\/strong>, with over 400 members worldwide and possibly again as many disputed or newly-discovered species.<\/li>\n\n\n\n<li>The genus includes the common (\u201cbutton\u201d) mushroom (Agaricus bisporus) and the field mushroom (A. campestris), the dominant cultivated mushrooms of the West.<\/li>\n<\/ul>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter is-resized\"><img decoding=\"async\" src=\"https:\/\/lotusarise.com\/wp-content\/uploads\/2024\/02\/Agaricus-1024x693.jpeg\" alt=\"Agaricus\" class=\"wp-image-48365\" style=\"width:705px;height:auto\" title=\"\"><\/figure>\n<\/div>\n\n\n<h6 class=\"wp-block-heading\" id=\"spirogyra\">Spirogyra<\/h6>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Spirogyra are&nbsp;<strong>free-floating green algae<\/strong>&nbsp;present in freshwater habitats such as ponds, lakes, etc. Spirogyra are commonly known as \u201c<strong>water silk or pond silk<\/strong>\u201d.<\/li>\n\n\n\n<li>They have a filamentous and unbranched vegetative structure. There are around 400 species of Spirogyra found. The genus Spirogyra is named after the unique spiral chloroplast present in the cells of algae.<\/li>\n\n\n\n<li><strong>Spirogyra are photosynthetic<\/strong>&nbsp;and contribute substantially to the total carbon dioxide fixation carried out. They increase the level of oxygen in their habitat. Many aquatic organisms feed on them.<\/li>\n<\/ul>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter is-resized\"><img decoding=\"async\" src=\"https:\/\/lotusarise.com\/wp-content\/uploads\/2024\/02\/Spirogyra-1024x632.webp\" alt=\"Spirogyra\" class=\"wp-image-48366\" style=\"width:692px;height:auto\" title=\"\"><\/figure>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>Which of the above is\/are used as&nbsp;biofertilizer\/biofertilizers? Answer: (b) 2 only Biofertilizers Nostoc Agaricus Spirogyra<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":""},"categories":[1,3],"tags":[44],"years":[60],"class_list":["post-1541","post","type-post","status-publish","format-standard","hentry","category-upsc","category-prelims","tag-science-and-tech","years-60"],"acf":[],"taxonomy_info":{"category":[{"value":1,"label":"UPSC"},{"value":3,"label":"Prelims"}],"post_tag":[{"value":44,"label":"Science and Tech"}],"years":[{"value":60,"label":"2013"}]},"featured_image_src_large":false,"author_info":{"display_name":"LotusArise","author_link":"https:\/\/lotusarise.com\/qna\/author\/team-lotusarise"},"comment_info":0,"category_info":[{"term_id":1,"name":"UPSC","slug":"upsc","term_group":0,"term_taxonomy_id":1,"taxonomy":"category","description":"","parent":0,"count":1269,"filter":"raw","cat_ID":1,"category_count":1269,"category_description":"","cat_name":"UPSC","category_nicename":"upsc","category_parent":0},{"term_id":3,"name":"Prelims","slug":"prelims","term_group":0,"term_taxonomy_id":3,"taxonomy":"category","description":"","parent":1,"count":1251,"filter":"raw","cat_ID":3,"category_count":1251,"category_description":"","cat_name":"Prelims","category_nicename":"prelims","category_parent":1}],"tag_info":[{"term_id":44,"name":"Science and Tech","slug":"science-and-tech","term_group":0,"term_taxonomy_id":44,"taxonomy":"post_tag","description":"","parent":0,"count":167,"filter":"raw"}],"_links":{"self":[{"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/posts\/1541","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/comments?post=1541"}],"version-history":[{"count":1,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/posts\/1541\/revisions"}],"predecessor-version":[{"id":1558,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/posts\/1541\/revisions\/1558"}],"wp:attachment":[{"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/media?parent=1541"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/categories?post=1541"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/tags?post=1541"},{"taxonomy":"years","embeddable":true,"href":"https:\/\/lotusarise.com\/qna\/wp-json\/wp\/v2\/years?post=1541"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}