Many plants need bacterial roommates to survive So why do some kick

first_img Many plants need bacterial roommates to survive. So why do some kick them out? By Elizabeth PennisiMay. 24, 2018 , 2:00 PM Sign up for our daily newsletter Get more great content like this delivered right to you! Country Email Olivier Vandeginste/Science Source When it comes to getting one of their most critical nutrients, some plants recruit tiny friends: soil bacteria that live in bumps on their roots and harvest nitrogen from the air. A new study reveals that these partners are expensive to keep, however, so much so that some species have given up on these microbial gardeners.Species from 10 plant families—including peanuts, beans, and mimosa trees (pictured)—all thrive in poor soils because they partner with so-called nitrogen-fixing bacteria. But plant biologists have long puzzled over why the other 18 families in this kingdom, and even some species within those 10, haven’t also evolved this beneficial trait.To find out, researchers sequenced seven genomes of nitrogen-fixing plant species and three closely related species that don’t fix nitrogen. They compared the gene makeup of these with 27 other plant genomes, 18 of them nitrogen-fixers. The analysis suggests the ability to form these partnerships evolved in the common ancestor to the 10 families that have this capability but was lost at least eight times after a gene key to the plant getting hooked up with bacteria mutated or was lost altogether, the team reports today in Science. These multiple losses suggest the nitrogen-fixing plants invest a lot of energy in these partnerships, so much so that if there’s enough nitrogen in the soil, they stop forming these partnerships and eventually lose the ability to form them at all.Nitrogen fixation is such a valuable trait that millions of dollars are being spent to endow crops with this ability. But the new work suggests plant scientists need to keep these potential costs in mind. Country * Afghanistan Aland Islands Albania Algeria Andorra Angola Anguilla Antarctica Antigua and Barbuda Argentina Armenia Aruba Australia Austria Azerbaijan Bahamas Bahrain Bangladesh Barbados Belarus Belgium Belize Benin Bermuda Bhutan Bolivia, Plurinational State of Bonaire, Sint Eustatius and Saba Bosnia and Herzegovina Botswana Bouvet Island Brazil British Indian Ocean Territory Brunei Darussalam Bulgaria Burkina Faso Burundi Cambodia Cameroon Canada Cape Verde Cayman Islands Central African Republic Chad Chile China Christmas Island Cocos (Keeling) Islands Colombia Comoros Congo Congo, the Democratic Republic of the Cook Islands Costa Rica Cote d’Ivoire Croatia Cuba Curaçao Cyprus Czech Republic Denmark Djibouti Dominica Dominican Republic Ecuador Egypt El Salvador Equatorial Guinea Eritrea Estonia Ethiopia Falkland Islands (Malvinas) Faroe Islands Fiji Finland France French Guiana French Polynesia French Southern Territories Gabon Gambia Georgia Germany Ghana Gibraltar Greece Greenland Grenada Guadeloupe Guatemala Guernsey Guinea Guinea-Bissau Guyana Haiti Heard Island and McDonald Islands Holy See (Vatican City State) Honduras Hungary Iceland India Indonesia Iran, Islamic Republic of Iraq Ireland Isle of Man Israel Italy Jamaica Japan Jersey Jordan Kazakhstan Kenya Kiribati Korea, Democratic People’s Republic of Korea, Republic of Kuwait Kyrgyzstan Lao People’s Democratic Republic Latvia Lebanon Lesotho Liberia Libyan Arab Jamahiriya Liechtenstein Lithuania Luxembourg Macao Macedonia, the former Yugoslav Republic of Madagascar Malawi Malaysia Maldives Mali Malta Martinique Mauritania Mauritius Mayotte Mexico Moldova, Republic of Monaco Mongolia Montenegro Montserrat Morocco Mozambique Myanmar Namibia Nauru Nepal Netherlands New Caledonia New Zealand Nicaragua Niger Nigeria Niue Norfolk Island Norway Oman Pakistan Palestine Panama Papua New Guinea Paraguay Peru Philippines Pitcairn Poland Portugal Qatar Reunion Romania Russian Federation Rwanda Saint Barthélemy Saint Helena, Ascension and Tristan da Cunha Saint Kitts and Nevis Saint Lucia Saint Martin (French part) Saint Pierre and Miquelon Saint Vincent and the Grenadines Samoa San Marino Sao Tome and Principe Saudi Arabia Senegal Serbia Seychelles Sierra Leone Singapore Sint Maarten (Dutch part) Slovakia Slovenia Solomon Islands Somalia South Africa South Georgia and the South Sandwich Islands South Sudan Spain Sri Lanka Sudan Suriname Svalbard and Jan Mayen Swaziland Sweden Switzerland Syrian Arab Republic Taiwan Tajikistan Tanzania, United Republic of Thailand Timor-Leste Togo Tokelau Tonga Trinidad and Tobago Tunisia Turkey Turkmenistan Turks and Caicos Islands Tuvalu Uganda Ukraine United Arab Emirates United Kingdom United States Uruguay Uzbekistan Vanuatu Venezuela, Bolivarian Republic of Vietnam Virgin Islands, British Wallis and Futuna Western Sahara Yemen Zambia Zimbabwe Click to view the privacy policy. Required fields are indicated by an asterisk (*)last_img read more